I'm concluding any reliance on App Store promotion is a non-starter. Get out and advertise the app! For months I drove past a big Road Ninja app billboard. Our company's app (granted it's more of a service than just the iOS app) is being promoted to success with zero App Store visibility - requiring a substantial sales/marketing team. With over a half-million apps available, there's just no sense in expecting the App Store will make it easy to find yours. Don't just put it there and hope it sells, get out and advertise it!