1. This is a very limited subset of conferences/fields. 2. Google Research is younger than Microsoft Research. 3. Google Research is really mixed with their product development whereas Microsoft (and IBM) Research are more isolated so they can focus on fundamental research and publications (there is some transfer...). A Google representative once said in a software engineering conference: "Come work at Google Research, you'll work on real and interesting research problems like GMail". Gmail==Research? Really?