It's a bit lacking in functionality for my taste, and it's not laid out the best, I've seen examples of it and it looks far too basic.
In case anyone is wondering the plans they've been posted here now:
Web Hosting Talk - View Single Post - Leaked vBulletin information, what do you think [MERGED]
Basically anyone who wants to install vB4 has to pay them almost 200 dollars to upgrade regardless if they have a license already or not.