If I understand things correctly we probably wont need custom templates to make phpbb3 look like your Joomla site. I mean for those using the bridge once it's done.
Johan Janssens wrote:
In my previous blog post I also hinted about a little surprise. Well, the good news for RokBridge users is that we (thanks Anthony) have found a way to visually integrate the bridge into Joomla! 1.5 without using a component. This means full performance, user bridging and visual integration. Neat isn't !
From this article:
blog.joomlatools.org/2008/04/building-bridges-using-joomla.html