She'll be 70 in '16. 2012 is her last chance so she'll trample anyone in her way to get it.
To get what? She can’t be President in 2013, and she doesn’t want to be VP. For Hillary, the VP-slot is a means to an end ... and, in this case, it won’t get her closer to the desired end. Obama is in her way. Being his running mate doesn’t help her.
I wouldn’t put it past her to run at 70. I think she’d refuse the running-mate offer, though.
SnakeDoc