Maybe she'll get out, but I would bet she's got another Senate term in her. She's really not that old, certainly not as far as the senate is concerned. Hell, Strom Thurmond was what, 162, when he retired?
And I don't think money is the only reason she won't run as an independant. I think she is a loyal democrat, and she's being honest when she says she'd rather see Obama than McCain. I just think the money makes it impossible.
Besides, she'll wield more power as Senate majority leader than she would as a failed Presidential candidate.