I am a high level Platinum / low level Diamond player (end of beta phase 1) with Protoss as my primary race. I have been playing games for what seems like an eternity, though I stopped playing SC:BW when WoW was released.
During the downtime, I have been playing Final Fantasy 7 and a little of 8, League of Legends, Heroes of Newerth, and other random games like Audiosurf and Beat Hazard. When phase 2 begins, I will be playing Starcraft 2 almost exclusively, with some minor breaks here and there for the games I am playing during the downtime. This is likely to be the same method I use now upon release - exclusivity for Starcraft 2.
During the games, I commentate a little, though I have been known to start talking about things in the game (and demeaning myself for losing to scrubs) quite often... especially if I fuck up hardcore and lose to what I consider a bad player, though it is hard to actually describe what I think that actually is.
I listen to music alot during SC2 games, though not when I am trying (and failing horribly) to commentate a replay. The music I have playing when I cast is usually 181.fm's Active Rock channel, though I do on occasion listen to a variety of other music, including freestyle (the Pure Pleazure kind, not the (c)rap) and pop.
The chat is usually active as well, and I participate in the chat quite often, especially between games.
edit: answered the questions AbyssV3 posted =)