Earlier today, TechCrunch broke and confirmed the story that BumpTop has been acquired by Google; the terms of the acquisition haven't been announced. BumpTop (not to be confused with the Bump application for the iPhone) is a 3D user interface for tablets and touchscreen PCs that works on Windows and Mac OS X. The company has announced that it will discontinue its existing software and will provide no further updates for those products.
The following video provides a good demonstration of BumpTop's capabilities:
There have been a lot of questions about how Google would adapt Android for tablet applications, or develop a separate user interface for Chrome OS. BumpTop would provide an excellent tablet user interface for either operating system, and would give Google a running start in its battle with Apple.