If you visit Google's 'about Android' page, you'll see a full-on Kit Kat bar (the company uses 'Kit Kat', not 'KitKat' to describe the candy) with an Android-themed wrapper. A link to 'see what you've won' leads you to the U.S. site for Kit Kat bars. read more
Well, it's right there on the page - it's a cross-promotion deal between Android (who get to use the name of the candy in their software) and Nestle (who get the promotional push and sell a "branded" limited edition Android Kit Kat). read more
Interestingly, the link on the Android site takes you to Hershey’s site, even though Nestlé manufactures Kit Kat bars in most of the world. This stems from an old licensing deal between Hershey and Rowntree (which was acquired by Nestlé), in which Hershey maintained the ability to license the name Kit Kat in the U.S. read more
* As a part of the deal, KitKat bars that would now come will have special prizes where people can win the Nexus 7 tablets, or the different goodies if they luckily find it in the cover of the KitKat chocolate. read more