One of the big SEO issues with forums are paginated threads in general. Google is only going to rank the first page in the thread well. I've just about never seen a non page 1 ever show up high in search results. Does anyone know if Google crawls all pages of a thread and evaluates it's entirety and then ranks if the first page accordingly? I doubt it. That means if your first page of every thread is not awesome, you're stuck. If you have amazing content scattered around 30 pages of a thread, sorry, you're out of luck. That is the key to up/down voting. It sucks for discussion, but it forces all the best content to the first page and high up the page. If anyone has a solution to this you'll be very rich. As of now there is no good solution to marry threaded discussion with up/down voting or any other quality content raising methods.