Mario - NSMB DS and Wii, Galaxy? All amazing, all better than last gen by far. Sunshine was a bomb.
God of War - The Collection and the demo for 3 are amazing, so I'll say push because 3 isn't out. It could be the best of the series though, the demo was sick, so we'll see. We also had the PSP game this gen, but it's still a push.
Resident Evil - 4 is IMO a top 5 game of all time, so it's worse. I still had a lot of fun with this gen's game though.
CoD - We had 4 (amazing), WW (total crap), and MW2 (also terrific) vs. CoD 1-3. Edge to this gen, but barely. CoD 1 and 2 are amazing, 3 was awful, so each gen has a bad one and two great ones. I just played CoD4 more than the rest combined.
It's been a great gen, really. Underrated if you ask me, especially with the new IPs (Uncharted, Bioshock, Dead Space, Assassin's Creed [only the second one], and a ton more. LBP too)