Joel I think you should think about your idea a lot first. I follow you on your blog and you happen to jump from project to project and your mind just can't settle with one on the long run. How about planning the business first with all the legal things (which everybody hates and leaves the last). After that you may see if it will be a success or not. Read back your ideas and look at why they change every day :) If you have one for more than 5 days than that will be the winner!
But that's just my 2 cents.