If I have to pick a certain company, it'd either be Bioware, Blizzard or Squeenix. My personal favorite out of the 3 would be Squeenix, but Blizzard would probably take the win for most. Squeenix scored big and introduce gaming to millions with FF7, Bioware is PC hardcore's favorite, but what Blizzard did was nothing short of incredible. Their achievement is so great, it transcends just gaming history. I believe that one day, their name will be as big a part of our history as AT&T or George W Bush.
But if I don't have to pick a "publishing" developer, I would go with me. Who else make games that I deem perfect? Too bad none of my games ever got out of my head, hehe.