MyBB Community Forums

My suggestion is to create a private message system as topics (similar to facebook).
When I send a PM to an user, if he reply, his message will be shown under my last message.
Ajax would be fantastic in this, like quick reply.

http://community.mybb.com/thread-99746.html

It's on the list.

I already read that, but there's no details.
I suggested to make a tiny system like facebook, using ajax.
By the way I know the mybb's developers are very exceptional and trusted!

"Conversation PMs"

That means they will show like threads are.

It's not going to be like Facebook's though. That would just make it bloated, and for active forums it would noticeably increase the bandwidth usage.

Maybe because facebook system update the conversation every determined time?