The only way this would work is if it were an FAQ thread that no one but the moderators could edit. How else could you possibly maintain any sort of structure to the thread? You can't post immediately after the FAQ topic if you have a related question - it goes to the end of the pile.
Soon the FAQ thread becomes as disjointed as any other 4,000 post thread about the new iMacs or whatever.
But if only moderators could edit it, how do you add new FAQs or ask about an existing one? Oh, you start a new thread.
By the way, I'm hoping to get a new Powerbook next week at work, but I don't know if I should wait for the upgrade, and if so how big a deal it will be and if I should go 12" or 15". I have an external display to go with it, but I might also need a new one...