I would say Demon's Souls, but I didn't play it long enough to really give it justice (Killed by a dragon on a bridge 30 minutes in.)

Gran Turismo 5 - The special challenges and getting gold on all the license challenges is brutal. I need a wheel.....

Killzone 2. Specifically, the last level (including boss). I hadn't realized that the enemies continuously spawned until a few hours in and I had only moved up a few feet. It took me the entire afternoon just to get to the boss because of that. Then Radec himself was a real pain.

Haha you got me there. I meant BEST PS3 GAMES EVAAARRR!

I don't know... Vanquish on God Hard? I don't think this gen has many challenging games... the hard mode of today seems to be what the normal mode was like last gen most of the times.

The hardest ones last gen were God Hand on Hard and Devil May Cry 3 on Dante Must Die for me... but Devil May Cry 3 doesn't feel hard anymore.... that leaves God Hand as the hardest one from last gen... but not as hard as it used to be :S maybe I just got better at games with time or something.