Are we listing publishers or developers?
EA is naff (nice way of putting it), purely as they use their marketing potential but don't back up with a good product or good support. After iteration 10 of said product it isn't exactly hard to think about how to design iteration 11 per se.
Case in point BF series. It isn't them that develop it, design it, it is just their money a lot of the time. It is still buggy, they lack the support it should get and don't make the expansion packs worthwhile beyond new models and new maps and try to charge you 2/3's the original price of the game for a quick knock up with each expansion rather than fixing the original issues. What a load of crud. This divides the playing community as well so the experience is lost and servers are harder to find with good players etc.
So no... ea suck.
Valve... take to long to deliver but eventually do. Bit like AMD, talk the talk but take ages to walk the walk. I still think they could have (and should have) done a lot better with the source engine. Good games developer over all.
Infinity Ward> Comes up with some real gems that pretty much run well (Read: Smoothly) and look good no matter settings you choose. Really goes with what the community is looking for. Feel they can get boxed in though, and really need to push the envelope a bit however.
SOE> Bring out good games, but has a habit of shooting themselves in the foot, a bit like EA really. Case in point: Planetside. Should have been monumental, and as for a while, but really screwed it up. Failed to fix basic issues, before trying to palm off expansions. Then really screwed it up with the segregation of the planets malarky. What the heck was that, talk about loosing their way.
Blizzard> Hope to see more games from them, but for the moment I'm sure they are just sat on milking as much as possible from WoW. Bring out fantastic game play products, a bit like the bit map brothers used to do back in the day, just need to polish up on the delivery of expected other titles.
Rockstar> Weak. It's easy to sell a 'bad boy' title when the advertising is heavy, and makes it seem cool. They sell their titles on controversy, so I rate it down their with Jerry Springer. Trash developer. If they actually decided to make a proper title I would definately be interested however.
There are loads of others I haven't mentioned but are listed in this thead. None are perfect, and those that are get lost in their own glory and occasionally come back to planet earth and make a blinding title. Others are one hit wonders.
Valve prob has to win it though purely down to market penetration with proper games, although they are currently in the sequel spiral and in danger of not getting out. I would like to see more cross company developments, stories from one company and coding/graphics from another. Crysis looked good but the scripting was awful and not very convincing. I haven't even tried the multiplayer lol.
Matthew