The original Ansari X-PRIZE offered a $10 million dollar prize for the first team to launch a reusable ship into space twice within two weeks. The Google Lunar X-PRIZE will be divided into a $20 grand prize, a $5 million second prize, and $5 million in bonus prizes. The X-PRIZE Foundation anticipates that "the first launch will be attempted within three to four years."
The recent introduction of Google Sky in Google Earth makes more sense as an X-PRIZE promotional tool.
Google has also kicked Google Moon up a notch with an improved interface, more features, and more detailed pictures. Sadly, they also removed the view of cheese when you zoom in too close. That was my favorite part.

