Have lots of features. But don't overcrowd. A page overcrowded with features is all too much. Also don't add complicated features. Remember you do get kids on all boards and intelligence deficient people... hehe
Get a clean and crisp style. Light and elegant and smooth. To be honest
www.webdesignforums.net started out for me as another boring site. But it's developed into so much more than that for me. The design is spot-on... It's unique.
But with such a big forum amy why are you asking this

?
- miSt