It would appear that the recently released Sly Collection was more than just a fond look back at a classic PlayStation 2 franchise. According to a teaser trailer that unlocks when players acquire all of the game's Trophies, Sly 4 is currently in development. How's that for kick ass?
The last we heard about a potential Sly Cooper 4 was in Sucker Punch's last game, inFAMOUS, where the title was teased in a very subtle Easter Egg. Not much happened beyond that, but this new teaser has pretty much sealed the deal. Seems we know what's coming from Sucker Punch once iNFAMOUS 2's wrapped up.
[Thanks, Super Freak]