Preview at WWDC likely in June, followed by September launch.
First iPhone 5 Unboxing Videos Posted as Reports of Premature Deliveries Begin
T3 has also posted a number of other videos showing off features of the iPhone 5.
A second video has been posted to the official YouTube account of Vodafone Germany. iFun.de noted that the video was pulled soon after it was noticed, but it has reappeared on the official Vodafone account.
Finally, a third awkward unboxing video has been posted by a YouTube user who tells us that he pre-ordered his iPhone 5 through Apple and that it was delivered by UPS earlier today. Apple's standard practice involves coordination with delivery companies to hold shipments until the official launch date, but it is not unheard of for a few deliveries to slip through these holds.
Update: Vodafone Germany has removed its video once again. We've replaced our embed with an alternate version.