Valkyria Chronicles and Little Big Planet are, in my estimation, worth the cost of the PS3 all by themselves. I can't answer for God of War 3 or the vaporware FF XIII games, since they aren't even out yet, but Folklore is decent, too.
A few other games worth a look:
Metal Gear Solid 4
Ratchet & Clank
Uncharted
Resistance 1 and 2
Siren
Pixeljunk Eden
Elefunk
Soldner X
Pixeljunk Monsters
Flow
Everyday Shooter
Wipeout HD
Linger in Shadows
And of course it's an excellent Bluray player, etc. etc. etc.