The board is opensource and currently being developed. You can find out more about it at forum.totalgeek.org - that is where discussions on it's development are being held.
It is still in the early stages of development and has a long way to got before matching vBulletin but it is going in the right direction. Give it a couple of months and the board should be pretty advanced.
Yea I just realised that after posting. I have been keeping tabs with the development of this board from the start. There have been a few good features added, like private messaging and who's online.
I think it's the little things that make vBulleting great. For example with vbulletin if you choose to recieve email notification when posting you will only recieve one mail telling you that there has been a post. You can then visit the thread read the posts and then leave.
I hope phpBB can match vbulletin as the price tag (free ) is very tempting.