For me, it was definetly Metal Gear Solid 3: Snake Eater. The epic boss battles (The End), great cinematics and cool story made it the greatest game ever IMO. Half Life2 was also real good.

I have Metal Gear Acid 1, Acid 2, MGS:PO, MGS: DGN (Not quite a game I know), Valkyrie Profile: Lenneth, Final Fantasy Tatics: The War of the Lions,Socom Fire Team Bravo 2, and Jean D'Arc.

I highly doubt that MGS4 would be delayed by something so trivial as rumble. Besides, MGS4 is one of the PS3's biggest titles, and IMO the biggest title of the year. I am quite sure that Sony has kept Kojima Productions in the loop about it's legal battle for the rumble technololgy and I would venture to say that Kojima has planned accordingly for whatever outcome was to happen.

And, Yes. Rumble is a very important feature. Try using the AP sensor without it. ;)