I personally like the old linear style of thread organization, not "threaded" view - mostly for the fact many people reply to the wrong post and it gets messed up. Plus, it tends to take up more screen space.
My favorite tip for the forums is the subscription feature.
If you go to "Quick Links" and click "Edit Options" it will take you to your forums options page. Scroll down to "Default Thread Subscription Mode" and select "No e-mail notification". This option will automatically "subscribe" you to any thread that you post in.
Now, for the key part of this feature. If you click "Quick Links" again and click "Subscribed Threads" it will take you to a list of all your subscriptions and show you which ones have new posts. The real tip I have to offer is to make that page your forum bookmark, instead of the index.
I have mine set up this way, and every time I hit the bookmark for the forums it takes me to the list of threads I have participated in so I can check for replies and answer questions.
The slight disadvantage is to see
new threads you do have to go out to the index. Luckily, from any page you can just click "Graal Communication Center" to go to the index, or any sub-level to check the forum you are in, etc. I only mention it because if you are a hit and run forum checker like me, sometimes you might not take the time to go check for new threads.
So what are your guys' tips on using the forums to maximum effectiveness?