I'm guessing this is all Visual C++ code?
I might be interested in doing some work on it. Have you thought about releasing the source to a couple of people, signing NDAs or something?
I'd like to work on it, but I'm not sure if I want the WHOLE responsibility (for time reasons, just as you described). This way you could maintain the web-site and all that and have a small developer base working on it. After all, two heads are often better than one.