Let's see...Valve made awesome games, and even provides some gratuitous extras on Steam. On the other hand, I'll set Gabe Newell's house on fire if I don't get any news on a HL2 sequel or EP3 soon. Or rather I would, if I had any idea where he lives. Google stalking ftw!
Then again, Bioware made the truly excellent Jade Empire, and has thus far failed to incite my pyromaniac urges. But, they went for the mmo instead of a KotOR3, though I'll wait until how well that turns out.
But let's go back a bit farther in time, late 90s, early 00s perhaps? What about Bullfrog? Or to you young'uns, the developer of Populus and Dungeon Keeper (that was before Molyneux became MS's ***** for hire)? Yeah, I'm gonna go with Bullfrog!