I've been watching the Olympics mostly on Romanian and Polish feeds. I can't understand anything the commentators are saying, but it's still great hearing the crowd noise and sounds from the competition. Muting the sound completely takes away the whole atmosphere of the event.
I think listening to the commentators is part of the fun. But then I haven't come across someone who was extremely annoying. When I watch feeds in foreign language, I may not understand what they're saying but the tone of their voice indicates if something interesting is happening (and sometimes, they do sound hilarious).
Sometimes I cannot stand the announcers because one their so bias or two they don't have a clue on what their talking about, but in the end I'll still leave the sound on because I believe it's better with the crowd reaction and someone talking.
When I see sports live it's so much different then watching them on television even though it's still enjoyable live it's better watching them with announcers.
I agree with pretty much everyone. I remember when I lost sound on my television set once and I had too listen to sports with no sound for a few weeks and it was awful...I actually couldn't take it. But I do feel some of the announcers talk too much and should just let the game flow instead of explaining every little thing that is happening.