Brad Wardell of Stardock has talked a lot on his blog about the development of Sins of a Solar Empire, and how it brought Stardock and Ironclad Games very close together, to the point where they could almost be considered one company. Stardock is technically the publisher but because they also develop games they could provide all kinds of help to Ironclad to get their game ready to go out the door – and the game certainly seems to have benefited, with a Metacritic score of 88.
Frankly, I think the two best game publishers on Earth right now are Stardock and Valve. Funny how both are developers as well as publishers. And funny how both use a combination of digital distribution and retail to sell their games.