Here's a great idea from Ryan Cash to put iOS apps unavailable for immediate download into a queue that will automatically resume when they can.
Ryan notes that he often buys iOS apps when he's out-and-about, whether it be on the recommendation of a friend, riding in a car, etc. The problem is many of the target apps are over the 20MB 3G limit. I've experienced this myself, as well as the inevitable conclusion: I forget to try again once I'm within a Wi-Fi network and the app's author has lost that sale.
Ryan suggests an "add to queue" option to accompany or follow the notification at right, which would put that download into a holding pattern until the iPhone found a Wi-Fi network. That way, the download would resume, we'd get that cool app we
