I think introducing live messages would complicate things. Its fine as it is. If you need to ask someone personally, you will have the option of sending them a PM.
namepros has one, and they seem to use it. But it's also a lot of domain spamming in there. Not sure it would take off at DP.
just create a channel on IRC #digitalpoint on efnet, thats free then try and convince DP to install one of those free java IRC clients
Chat room in DP. Very good idea. But if chat room exists on DP. It can effect the posts. Discussion through posts are forever. We can find any post any time. But in chat room our discussion is just for the min.(no record after logout) No one can see our chat discussion in long.