Jennifer Saranow wrote a piece in The Wall Street Journal today entitled "Your Space is Waiting: Reserving a Parking Spot." Several companies were mentioned, including MobileParking LLC and SpotScout, among others. The value proposition of reservations models was challenged in the article, and that type of service has been offered by others that didn't survive the dotcom meltdown.
CarHarbor has no interest in the reservations model. It's simply too likely that such a provider will burn unsuspecting customers who end up passing numerous closer and cheaper parking opportunities as they walk from their reserved space to their ultimate destination. In addition, most of these start-ups plan to focus on loading inventory at parking garages, where there is almost always excess capacity anyway. Who wants to pay even more than the typically high garage rates for what is usually a free option? Most of the garages and lots I use, especially at airports, don't even have an attendant on hand to enforce a reservation system.