Oh, not as queer as you'd think, but I'm not downloading things all the time, so Steam is happy to run in the background while I surf Subsim or do whatever. The only time it causes a hinderance is if it suddenly decides to download an update whilst I'm playing a multiplayer game...
Rather than a player, Bigscreen is more like a multiplayer social interaction platform with movie watching at its core. Online resources are abundant, with movies, TV shows, YouTube and everything else, and you can invite or join other players into the virtual theater to watch movies together...