I don't play very many games, but the ones that I do play I absolutely love. So for the next Batman, Uncharted, Assassin's Creed...if they're only available on the PS4 and NOT the PS3, I'll probably find myself upgrading.
I just wish there were more reasons to upgrade. My PS3 is one of the best purchases I've ever made, not because of the games, but because of the Blu-Ray player and WiFi capabilities.