And what I'm supposed to do with the source code? Relaunch it as another product and try and compete with Google? Free source code is the oldest trick in Google's book, it amazes me people still fall for it.

Just out of curiosity, does anyone know of an example of a successful startup whose products are based on source code from Google?

Would you rather just have documentation of APIs? Having the source code is better than not, at least it gives people the option to expand/correct/port anything if they wish to.

Would you consider Linux a successful open source project? I imagine the greatest impact has not been people relaunching "Linux Pro", but people who have built off of it.