I think it would be a good idea indeed. The problem will be getting enough users to regularly visit it, otherwise you'll end up with a lot of unanswered questions, and questions taking longer to answer than they would if asked in one of the main forums. You can see this effect already on some of the other resources that have started up in recent years - amigacoding.de for example.
On the other hand, it might be worth an experiment, and I do think it would be a valuable asset if it did take off. I can't dedicate too much time to it, but I'm happy to follow it and answer the odd question when they pop up.