According to a large number of vanitites posted on this board Obama is to be preferred over the likely GOP nominee. To this end they are tirelessly giving Obama and his supporters issues to exploit against the GOP nominee. There comes a time when those whose candidate has lost to acknowledge the democratice choice. Acceptance does not equate to enthusiastic support.
I'd be curious to see the overlap between the "I'm sitting this one out" and "Obama won't leave office" crowd.