I think The Situation has to be considered the favorite here. His abs are sort of his thing, other than his ability to sum up lifestyle choices with three-letter acronyms. In Bret Michaels' case, he is best known for his bandanna and the way he used reality television to find a life partner.
But then, seemingly out of nowhere, he showed up on the cover of Billboard, sans clothes, and shocked the world with his six-pack.
Which brings us to the here and now and this question. Who has better abs!? Vote in the poll and add any useful commentary to in the comments.