Oftentimes my advice is asked for. I'm actually starting to get a reputation for being a good helper: A friend of mine who I'm going too will tell me about this goddamned level he simply hasn't been able to beat for weeks, he tries it again, with me giving a few useful pointers, and suddenly he's beaten it.
Of course, it isn't always asked for, and it can piss people off, though some people are worse in this regard than others. Sometimes I need to tell my brother to back off and shut up, because his constant ordering me around is taking all the fun out of the game. I'm not very good at taking other peoples advice anyway.