There has been lots of talks about the possibility of a chat, many of us have requested it. I know they are working with partners for better implementation of existing ones, such as Jbolo. That being said, no official confirmation or release date has been announced regarding an in-house chat. So for now, having tested Jbolo, CometChat and ArrowChat's latest versions on EasySocial 1.2, I can confidently say that currently CometChat is the one to beat... but I know the developers of JBolo are working closely with Mark to improve their implementation to a greater degree, so in the future it might be the one to beat... but for now CometChat, their latest release was surprisingly good. That said, none are fantastic yet :P
... that said, with Mark and Stackideas you never know, they might surprise us... so take what I said with a grain of salt.