I bought a brand new PS3 Slim 160GB a week ago and out of the box gameplay was laggy. It seems to be significantly worse when there is fast movement/fine detail in the game. There are no problems with the main menu, DVDs, or BDs. It has the same problem wit any tv withe the cable from the box, but I have no idea about HDMI. No online play due to a slow connection. I have a 2 year old 120GB Slim that does the EXACT same thing. Games like L.A. Noire and Uncharted 3 are the worst. If anyone has any clue what the problem is, please enlighten me. Thanks.

This problem is not a ps3 problem.
It's not your games fault either.

It's your TV.

If you go into your tv options, try looking for an option for "digit clear motion(DCM)"
this lags the tv and the ps3 certainly gets lagged by it.