$30 million is very little (Score 1)

It's a shameless publicity stunt to attempt to maintain their image as a geeky startup which is fading rather fast. There is no reason for any private individual to get into this business right now, considering how difficult it is to get all the way over there. It's difficult enough to get your space shuttle in to outer space much less to the moon. In the event that this does occur, the 30 million will be chump change considering the billions that will have been invested in such a project. Therefore, I doubt Google ever even imagines paying out, they just write up a press release, get free publicity, and in the event that it does happen, oh well 30 million isn't all that much for a billion dollar company.
AP: http://ap.google.com/article/ALeqM5ioIwrLaUdgy0B2zqCnTzXswchBGA

The rules call for a spacecraft to trek at least 1,312 feet across the lunar surface and return a package of data including self-portraits, panoramic views and near-real time videos. Participants are also responsible for securing a launch vehicle for the probe, either by building it themselves or contracting with an existing rocket company.

Whoever accomplishes the feat by the end of 2012 will receive $20 million. If there is no winner, the purse will drop to $15 million until the end of 2014 when the contest expires. There is also a $5 million second-place prize and $5 million in bonus money to teams that go beyond the minimum requirements.

Is it likely that anyone will be out there by 2015 designing such an expensive craft, without some serious funding and motivation to do so? I seriously doubt it!