I think it's just because a quick google search can net you pics of Pam in a bikini, sans bikini, in almost any other attire imaginable, and even in her own porn. She's effectively worn out. Palin, on the other hand, is a fresh new face in the public eye. Besides, it's not often there's a female in politics one would *want* to see in a bikini at all. Granted, whether or not she's bikini worthy is totally subjective...but I still think it would be better than say, Pelosi.