Totally agree with what you said. But! "Most people" don't download apps the day they come out. Most people that end up downloading this app will be able to use it immediately. As it is, the early-adopting, first-in-lining, app-tweeting crowd is busy promoting this app to their friends by comparing their number in line -- effectively saying, without even having used the app: "man...this thing is really worth waiting for. better get in on it now!" I'd bet that their friends who download the app today ~won't delete it. They'll just close it. And get a push notification in a couple days telling them that they're in. That's tens of thousands of users they wouldn't have touched without this launch strategy.

Personally, I tip my hat to these guys for architecting this launch strategy...and cringe for the inevitable hoard of apps/services that will surely attempt to copy it.