Valve and Bethesda with the titles (for valve): Half Life 2, Half Life Deathmatch, Counter Strike: Source, DoD: Source, Left 4 Dead 2 and Portal.
Bethesda: Oblivion and the game that was quite good but ruined the entire series... You know the one I'm talking about.
Also, if SEGA had just produced Total War games, I would love them. Sadly, the ever growing t*rd stain that is the sonic series remains a burden on their shoulder. Would their ever be a way for them to leave sonic and focus on TW? - No because they milk sonic and not enough people buy RTS's.