Google + DoubleClick = GoogleClick
One consequence of Google's rather expensive acquisition of DoubleClick is that it turns the company from a search engine that sells ads into an advertising company that happens to have a search engine.
During Web 1.0, the accepted wisdom was that online advertising would never be viable as a revenue stream - the "real" money would have to come from somewhere else, such as subs or content purchased through micropayments. It will be interesting to see how things develop during Web 3.0...