I really liked using dnode, but I had serious scalability problems with it. I didn't have time to look too closely, but I found quite significant latency between sending/receiving messages to the extent that I just downgraded to using socket.io directly and was quite happy. Sorry to be vague, but it's been 8 months since I experienced the issue.

Definitely, give dnode a go. It's a lovely piece of software, but keep an eye out for performance issues.