I am new to this forum.
I came across JForum while looking for a discussion board engine for my upcoming site.
First great job on JForum and thanks for the hard work.
Second, please don't get caught up in debating too much on what technology to use.
Just get comfortable with whichever one appeals to you the most.
We all have our own preferences... hence, the various frameworks out there.
I will be releasing some tools and APIs on my site... some of which might be useful to you (in particular the Common Persistence API and the Render Tags).
I am also looking to help with development at some point (will have to free some time for that).
I have not had a chance to look at JForum v3 code base, but will do so next weekend.