Absolutely DO say hello (or whatever intro, like a firstname) and DO wait for the other party to respond. Why? Because I would hate to get "update: our quatere

Absolutely DO say hello (or whatever intro, like a firstname) and DO wait for the other party to respond. Why? Because I would hate to get "update: our quaterely results will be bad, we expect a 20% loss on our shares" popping up during a meeting just because I forgot to switch off the messaging app on my desktop. I may be someone who is expected to see that but possibly not the other 20 participants. A "ready for lunch?" can work without an introduction, though.