Miss your iDOS emulator, or another app that's been punted from the App Store? CDFXapps noticed that the App Store app on their iOS 5-enabled iPad gave them the option of redownloading the no-longer-available DOS emulation app. This is part of the new iCloud feature, already in place, that lets you re-grab your iTunes purchases if you don't have them locally (very handy if you lose your machine or your hard drive dies). Chris Welch also noticed that the original version of The Big Picture found its way back to his phone.
Meanwhile, Engadget spotted the option of redownloading the blocked iTris Tetris clone on an iPhone running iOS 4.3.3, so this particular privilege is not dependent on having the beta installed. This may not work for all apps, however; we tried to redownload a tethering application and couldn't get it. Perhaps there's a category for 'terminated with extreme prejudice.'
This is certainly handy if you've accidentally deleted or misplaced an app that you bought before it got pulled -- but chances are this particular loophole will get closed relatively soon.