I don't believe beating the hell out of strangers for no obvious reason is the sort of image that Abe as a character represents. Perhaps the Stranger could get away with it, but not- and I quote- "the skinny guy with no weapons". I'd be happier to see a playable Slig than Abe, or perhaps a Rupture Farms stage. You are right that Oddworld should be involved, though- the Abe games were a PlayStation classic.
EDIT:
http://www.psu.com/a016855/Oddworld-...tion-All-Stars
By the looks of that, it seems Sony are basically giving JAW the cold shoulder...doesn't bode too well!