So, I'm a PC gamer primarily. Buying a new laptop for my wife and we may get a Sony, which comes with a free PS3.
Trying to decide whether I should even open the box (and just pawn it on eBay) or if I should rent a few games to play on it first, or just keep it.
I don't have an Xbox360 (but I do have a Wii).
I know PS usually has some pretty good exclusives, but I never pay attention to console exclusives, so I don't know what's out there. Mostly looking for some lists of games worth looking at for the machine that I can't get on the PC.
The PS3 has incredible exclusives. Not sure what kind of games you're into so I'll just list some of the great games from multiple genres that I've enjoyed.
The obvious answer is the Uncharted Series. Some of the best story telling / acting I've seen in gaming.
God of War series is also a PS3 staple.
Heavenly Sword was quite good in both story (another game with great acting) and gameplay and I highly recommend it.
Demon's Souls is an amazing action RPG (although the successor Dark Souls is coming in full console port force in August to the pc)
Heavy Rain was very unique and thought provoking. The gameplay is kind of slow, but the story is incredible and very thought provoking. I often found myself asking, "what would I do in this situation". It has something ridiculous like 20 different endings to the game dependent on your decisions and actions. Your story could play out differently than mine. If you get this game, my recommendation for the best possible experience is to let the game play out and avoid reseting / reloading old checkpoints to get the "optimal" outcome.
InFamous is a fun open world super hero type of game that offers some interesting gameplay.
Little Big Planet and Rachet and Clank if you like platformers.
Metal Gear Solid 4 if you like stealth / action games.
The MLB series is the best baseball game on the market.
Resistance Fall of Man for a first person shooter (I found the games meh, but some really like the series)
SOCOM Confrontations for some really fun third person multiplayer (high learning curve, but I loved this game).
The new Starhawk game is pretty fun if you're into multiplayer (the sp is basically training for mp)
Well, I don't know if you are an EVE Online player, but Dust 514 is a PS3 exclusive F2P shooter which ties in with EVE Online. The EVE players sell weapons and vehicles and stuff to the Dust 514 players, and its supposed to be pretty good. I think its in beta right now.
I'm also primarily a PC gamer, but some friends have PS3s and my favourite exclusives are probably Metal Gear Solid 4, Little Big Planet and Uncharted. I didn't think I would like Little Big Planet, buts its pretty awesome. Definitely something you can't get anywhere else. The Last of Us is also coming out, which should be cool. Its a post-apocalyptic zombie thing. Its being developed by Naughty Dog, the people behind Uncharted, so its supposed to be good.