Seriously, though, I fairly solidly hate the whole IM etiquette thing. Not the concept per se, but the petty and irrelevant way it has evolved. "Don't just say Hi and then disappear for hours" - that's real etiquette., not bollocks about punctuation or whether to say U or "you".
My bugbear is the "Hi" then no reply until I respond, followed by "Can I ask you a question?". Just say hi, ask the question and wait. There's no reason for this drawn out bullshit.
Seriously, though, I fairly solidly hate the whole IM etiquette thing. Not the concept per se, but the petty and irrelevant way it has evolved. "Don't just say Hi and then disappear for hours" - that's real etiquette., not bollocks about punctuation or whether to say U or "you".