I have played on Steam, battle.net, PSN, XBL and SegaNet.
Okay let's da a short comparison:
Steam is a good online store, but that is it. Try to play CounterStrike on Steam for more than 45 minutes without having at least 3 people cheating. The social aspect is limited and of course being on PC means you have to use different software. On a public server the chat options are terrible and so is the quality. And most games don't even support it. So most of the talking is done via another software like TS2, Ventrilo or even Skype. So you need to talk which TS2 / Vent IP you have to use. This alone kills the fun. You actually have to prepare your spontaneous gaming session if you want to caht. And whenever another player beats you (no matter if public or private) you still don't know if the other player plays fair. Of course the interface is not userfriendly at all.
Battle.net is a more basic version. I still play Warcraft 3, because the game is just fantastic. The average search time can be up to 5 minutes, but that is fine for a game this old. The problem is more or less the same: Cheaters. MH seems to be pre installed on Russian PCs. It is a mess. The problem with the chatting is still there. Vent / TS2 / Skype.
PSN is not user friendly. Yes, all of us are nerds, because we spend our time in gaming forums. The majority of gamers is different. The Apps are not well integrated and the social aspect is missing. Game chat can be used, but not everyone has a headset (same problem on PC btw). The bad part is that cross game chat is not available. The worse part is that the cross game chat won't be available due to lack of RAM. Futureproof hardware, heh? Not having cross game chat is simply not an option in 2011. The PSN games don't have a demo, there are not a lot of Apps. Yes there is a browser, but whoever considers that a great solution should be permabanned. My smartphone has a far better browser. Don't get me started with the PSN hack, updates, downtimes etc. PSN is behind XBL in every segment. It is free, have fun with it, but it is not as good as XBL.
XBL is by far the best service I ever played on. The chat options are perfect. There are hackers (there always will be) but those are limited. The way the Apps and the interface are built is just awesome. It always feels like one source, even though MS did not develop these Apps. The advertisement some people mention is just not a big deal. People like to dramatise this. The way Kinect works is brilliant so everybody wants to use and try it. All the Arcade games come with demos. Beacons are awesome as well and really push the social aspect. Additionally the customer service is very good as well. I had one issue with one movie a couple of years ago and it was handled very well. I received my money back in a couple of minutes. It really feels like a overall good service and a great experience.
Imagine not having GamePass on your console...
