I don't recall exactly, but I believe it was uninstalled because it was using too much resources.
I completely agree, though. I've said this since day 1; a shoutbox is not a chat. It's harder to keep up with, the shoutbox has bugs because of the alpha version the forum is running on, etc.
I don't understand why they haven't installed the Cyb chatbox... it worked fine for OVMK, even when 40+ people were in it.