" Only a small portion of uninsured citizens will actually be able to purchase the best Plan available in the Health Benefits Exchanges (the Platinum Plan)."
The four insurance Plans available in the American Health Benefits Exchanges are structured as follows: a Bronze Plan pays 60% of medical bills; a Silver Plan pays 70% of medical bills; a Gold Plan pays 80% of medical bills; and a Platinum Plan pays 90% of medical bills. Each of the four types of insurance Plans will cost a different amount, based on the "actuarial value" of the Plan. Actuarial value is a measure of the level of protection a health insurance policy offers, and indicates the percentage of health costs that, for an average population, would be covered by the health plan. Government issued tax subsidies will be provided to help eligible citizens to purchase one these four insurance Plans. These tax subsidies are supposed to make insurance premiums more affordable for each of the Plans. However, in the final analysis, only a small portion of uninsured citizens will actually be able to purchase the best Plan available in the Health Benefits Exchanges (the Platinum Plan). 
The independent Congressional Budget Office (CBO), in March 2012, estimated that the PPACA will leave up to 31 million people completely without health insurance, and lacking access to "affordable" health care.  In 2010 the CBO estimated that 29 million citizens will be served by the American Health Benefits Exchanges.  Since there are four Plans in the Exchanges, and we have no sure way to know what proportion of any given Plan will be purchased by eligible uninsured citizens, let's generously assume that - or 25% of the estimated 29 million eligible citizens (7.25 million people) are able to end up purchasing the best insurance Plan (a Platinum Plan). That will mean the remaining 75% of the needy citizens, or approximately 21.75 million citizens out of 29 million) who are eligible for PPACA Insurance Exchange Plans will end up with a purchased product that is inferior to the Platinum Plan (e.g. a Gold, Silver, or Bronze Plan). So right from the start, about 3 out of 4 citizens will have a Plan that will not ensure that their health care costs will be "affordable" when they get sick. 
What proportion of the entire uninsured citizenry will be adversely affected by the inequity inherent in the American Health Benefit Exchange ? Well, as of 2011, about 48.6 million American citizens had no health insurance at all.  Out of the total 48.6 million uninsured citizens in the U.S., if only 7.25 million uninsured citizens is able to obtain the very best Health Benefit Exchange Plan -- the Platinum Plan -- that will amount to only 15%, or 1 out of 6, of the 48.6 uninsured citizens. The other 85% of the uninsured citizens (41.35 million people) will get saddled with a health Plan that is inferior to the Platinum Plan. This indicates that the PPACA will not provide 5 out of 6 uninsured American citizens with health insurance Plan coverage most capable of meeting their medical needs. Moreover, the most likely scenario is that poor and near-poor Americans (including Black and Brown Americans) are least likely to obtain a health care Plan in the Health Benefit Exchanges that will make their health care costs "affordable" when they get sick.  And I have argued elsewhere, inequities in citizen's access to quality health insurance coverage create a significant amount of preventable lethality in the health care system.  This is how the PPACA fosters discrimination and injustice in healthcare access. Given the discriminatory and unjust aspects of the PPACA initiative, perhaps a more accurate name for the PPACA legislation is "Obamacare for the Few and ObamaDon'tCare for the Majority."
" Right from the start, about 3 out of 4 citizens will have a Plan that will not ensure that their health care costs will be "affordable" when they get sick."
The other clearly unjust section of PPACA pertains to the "expanded" Medicaid program. The Medicaid program provides for the cost of health care for poor children and their families, and people with certain disabilities.  The PPACA legislation is written such that at least 3 million eligible poor children may be unable to receive Medicaid services after 2017. Under PPACA, States that want to participate in an "expanded" Medicaid program will be required to pay for a small percentage of the costs incurred for new Medicaid patients starting in 2017. But in their February 2012 decision on the constitutionality of Obamacare's individual mandate clause, the SCOTUS affirmed the right of the States to opt-out of participation in an expansion of the Medicaid program. Because of the financial burdens placed on the States to pay a portion of the costs for enrolling new Medicaid patients, at least 13 States say they may opt-out of the Medicaid program for new patients.  As a result the CBO estimates that at least 3 million new eligible people will be uninsured.
And importantly, my estimates of the number of people who will be treated unfairly under Obamacare do not take into account the approximately 25% of INSURED workers who already have inferior and costly health insurance Plans through their jobs. Many, perhaps most, of these job-linked Plans do not ensure that the worker's health care costs will be "affordable" when they get sick. Indeed, when we combine the number of uninsured and under-insured citizens, a conservative estimate is that well over 100 million American citizens will NOT be covered with a health insurance Plan that makes their health care costs "affordable" when they get sick. The lack of adequate medical coverage will motivate a certain portion of these 100 million people to forego or delay attention to their medical problems,  which can be deadly in some cases. 
" At least 13 States say they may opt-out of the Medicaid program for new patients."
Some defenders of the program will say, "Well at least 7.5 million people are getting something from it. That counts for something!" Of course it does count for something. It does make a very small dent in reducing the number of people who are suffering because of health insurance challenges. It is wonderful to see perhaps 15% of the neediest people being protected from life-challenging health situations. At the same time, what is not sensible about Obamacare is:
(1) It adds to the U.S. budget deficit because the PPACA program requires a financial outlay of $2 trillion to implement. This huge amount of money will increase the drain on the GDP to an unsustainable level. By spending such a dramatically large amount of money to cover such a small percentage of needy people (15%), the program will likely come to be seen as inefficient and unsustainable. "Obamacare for the Few and ObamaDon'tCare for the Majority" is going to be subsidized with taxpayer dollars and will cost taxpayers and the federal government over $2 trillion dollars between 2012 and 2021, according to the Congressional Budget Office. 
(2) It ensures that most American family's personal resources will continue to be tapped to unsustainable levels for health insurance costs -- if they choose to have health insurance at all. Even if they don't have insurance, their income taxes are likely to be spent on getting other people insured with private insurance.
(3) It ensures that over 85% of the American people who need access to affordable, quality health care insurance when they really need it for catastrophic health problems still won't have it.
What is the solution? The solution is a publically-led, single payer, Health Care system that takes the profit-motive out of providing access to quality health care, and uses the billions that are saved to provide ALL our citizens with access to quality health care. As of 2009, about 50 countries had already attained Universal or near-Universal health coverage for all their citizens.  Yet in 2012 we in the U.S are the only developed, industrialized country in the world that still doesn't have a Universal Health Care system.  Instead we have Obamacare -- a discriminatory, expensive, and lethal corporate controlled profit-driven system that fails the majority of its citizens. Health care corporations don't want Universal Health Care because it will not be profitable for them. They dictate their terms to the government politicians, not the other way around. BOTH political parties do the bidding of the health care corporate edifice. Ralph Nader once noted: "The only difference between the Republican and Democratic parties is the velocities with which their knees hit the floor when corporations knock on their door. That's the only difference."
" We in the U.S are the only developed, industrialized country in the world that still doesn't have a Universal Health Care system."
We must find a way to rid ourselves of the control that corporations have over our politicians and over our health care system. Every year scores of thousands of lives depend on it. We must resist policies like PPACA that put trillions of dollars into the pockets of the health care industry, but don't serve the health care needs of most Americans. Every day the PPACA fosters preventable lethality -- citizens die because of barriers to quality medical care. This has prompted some health activists to argue that Health Care for All must be seen as a major civil rights issue. 
Reputable economists agree that the health care system we have now is "flawed" in its economic logic and is ultimately unsustainable. [24, 25] The most economically sustainable and just policy solution is to establish a Federal-or State- level public, not-for-profit universal health coverage system.  At the federal level, Congressman John Conyer's HR 676 or the Senate's American health Security Act are examples of initiatives that will utilize a government not-for-profit universal health coverage model (e.g. Medicare for All). At the State level, California's SB810 is an example of a government not-for-profit universal health coverage model. The health care industry, along with the politicians they have given money, will mightily try to thwart our efforts. But the battle must be waged for citizen's health and well being. Otherwise, we will sadly muddle along with "Obamacare for the Few and ObamaDon'tCare for the Majority"