I was thinking with the recent progress in AJAX programming etc..

Not gonna explain what that is, but Message boards / Forums will eventually evolve into something more powerful to use with better features. I think the following would be cool to see:

Avatar could remain static image or a small live video feed of your ugly face

Ms paint or basic level photoshop tools in the reply box so you can deface, high light or add text to pics on the fly

Record button for audio in 30-60 second intervals. Imagine what that could do for the audio booth.

Social network side bar - The ability to be in mid debate on a topic and be able to notify outside sources you personally know and invite them instantly into the thread.

Virtual nudes trapper keeper

Real time "contradiction stats"

Community table. A canvas type area where you can drag and drop certain multimedia files onto it which are represented by a certain icon. Anyone can drag items around. There could be a shelf life for the files with an expiration download date set by user/mod.

Public Ugly/beautiful stats - Zach Morris Looks being the highest achievable stat

USB Breathalyzer + open source forum software to support it - If you're way over the limit you cant log in unless 3 people vote yes.

Personality filtering - The ability to filter out people who fit criterias like (unfunny, smartass, too smart, too dumb, religious obsessed, conspiracy theory addicts, fat, skinny, chunkula, skin color, bone structure, back packer, drug user, drug dealer, pusseh, stalker, or better than you)

Annotations - To be able to add your own to peoples posts. You could rephrase what they really meant to say or just make fun of them and correct grammar!