It's a pretty big fail when people wait until the daily stand-up to communicate. It's better than not communicating at all, of course :-)

Either way, daily stand-ups are the worst thing about scrum especially when they are hijacked by PMs. I'm yet to meet a develop who'd look forward to stand-ups. I know they exist somewhere :-)

If you are curious about what other people (you don't talk to a lot) are working on then Hubot is a good solution. Hubot has a great plugin to let you share what you are working on without having to deal with stand-ups.