It is certainly an interesting concept, one that has worked in other places. Dockwa is available in other areas and essentially does the same thing.

One thing that I think could work great if it was part of it would be being able to make a reservation and cancel at anytime. The catch would be that if you cancel and no one else takes over your reservation, you still pay for it. But if you cancel and someone else books an otherwise full mooring field, they'd take the mooring you had reserved and you'd then get a refund. Would be great if there was a waitlist in a full mooring field as well - someone cancels, you get a notification..etc. Lots of potential. Only realy drawback I see is that it requires having an internet connection and not everyone will have it.