Regardless of who actually invented mapping parties, I felt that Google grabbing the idea and using it to promote it's closed community was really an example of his main thesis.

Imagine if Google held code sprints for it's commercial products and enticed people with t-shirts and bottled water, keeping their work for commercial use? Wouldn't you rather have those people participate in an open source project so that their volunteered time could be used by all rather than just Google?