Short but sweet.
It's fundamentally irrelevant whether or not Congressman Specter's switch is good for democrats or republicans. Where does, or where would the difference lie? It's presumable that his political philosophy did not alter merely overnight; That this has been a change that Specter has been considering for some time. And, that said, it's also presumable that his mentality, thus his political and ideological mindset, had for quite some time now already been altered, at least to a degree.
The result: Specter's political postition had, as well, manifested itself into the mainstream of democratic postinions. His recent change is merely reflected in name only. The deed has been ongoing. The fundamental problem rests on Specter's disregard for the agenda for "the people" he supposedly represents. While republican voters elected him, he never represented their views, nor their best interests.
In the end, it only serves to affirm that those, at least a majority, who serve in congress supposedly to represent the best interests of 'the people" do not. Rather, they serve only themselves and those who can further their political and financial gain.