As of June 2011, Google has roughly 740 million visitors per day. According to the release, during the two days the playable and recordable doodle were online, those visitors spent an average of 26 seconds more on the Google homepage than they normally would.
Running the math – 740 million times 26 seconds over two days – brings the total to nearly 10.7 million hours spent playing. Assuming the average Google user earns $25/hour, the release claims that the doodle cost companies around the world nearly $268 million in lost productivity.
The full report is available here.
Google has given the Les Paul doodle a permanent home here.