Looks like iOS 4.3, at least in the current beta, finally brings with it the ability to cancel app downloads/installs. Hit the App Store, start a download, and if you suddenly have second thoughts -- maybe you don't have time or bandwidth at the moment -- just tap and hold to enter jiggly mode and the X badge shows up on the downloading app. Tap the X, confirm you really want to delete, and the download and install stops and the icon vanishes.
Under current and previous versions of iOS, Jiggly Mode wouldn't provide the X badge for downloading/installing apps.
If you've just purchased the app you won't get refunded, of course, but if its a big game, huge navigation app, or for any reason you have second thoughts about downloading, you can now kill it and try again at a better time.
Small but great feature addition. Anyone else happy to have it?
For more, see our complete iOS 4.3 beta walkthrough...