I think the pre pay system for future sourcebook is a great idea....
In fact, I think it may be an excellent way to bring in future Delta Green, Wild Talents, Godlike etc. sourcebooks in the future.
Any chance of instituting a P500 type wargame pre pay system for future sourcebooks so the gamers and fans could vote(with their wallets) on what kind of books they want?
If it works well for wargames I think this can work equally well for RPGs.