See the below video to see Urs Hölzle annouce Google Compute Engine at Google IO 2012.
Sundar Pichai introduces Urs as one of the first 10 Google employees, the first VP of engineering, and the person more than any one else responsible for building all of Google's infrastructure (Data Centers, Servers, Network, and Infrastructure SW)
By the way I finally figured out how to embed a video and get it to start at a specific point of time, so this video will play at the 35m30s mark.
If you want to see the scale of Google data centers look at how small Urs is compared to the server racks. :-)
The video is the one I referenced with this post.