Bing's under Qi Lu. I guess the main reason is that a search engine by itself can not improve its market share. You'll need more channels to increase the traffi

Bing's under Qi Lu. I guess the main reason is that a search engine by itself can not improve its market share. You'll need more channels to increase the traffic. By giving more power to Lu, Bing can leverage other channels too like desktop search, enterprise search, etc. to increase brand awareness and traffic. Google is not just a search engine by itself. Most of everything else that Google does also aim to protect and increase search traffic.