1. Easily Bethesda for Skyrim, Oblivion, Fallout 3, and Fallout: New Vegas Worlds that sucked me in. Alos published Rage which is not in house, but it is a fun time.
2. Rockstar for GTA IV, Red Dead Redemption and Max Payne. Rockstar tries to make games not for kids. They seem unable to make a bad game even though I skipped L.A. Noir.
3. Bioware Mass Effect 2 alone gets this game on the list, but they also made 2 other greats in the series.
4. Naughty Dog They make the most polished games this Gen in the uncharted series.
Edit: 5. Ea's Visceral Games for Dead Space 1 and 2 Masters of terror this gen.
6. Rocksteady The Batman games arkham Asylum and prison make this studio the newest to the list of badass developers.
7. Valve The Orange Box, Left 4 dead series and Portal 2 are all winners.
Publisher/developer that lost me this gen Square Enix, The RPGs are just too feminine. I want games with sweet characters like in FF 7 were they were not all girly.