First of all, "cloud computing" is going to be a very low-margin business compared to ads. So comparing revenues doesn't mean very much. Second, pretty much e

First of all, "cloud computing" is going to be a very low-margin business compared to ads. So comparing revenues doesn't mean very much. Second, pretty much every Google business other than ads could be described as "running on Google cloud" for some definition of Google cloud. Apart from App Engine (which is a completely separate starting point than the rest of GCE and is really more of a solution to Google internal tools than to enterprise customers), the initial cloud offering can roughly be described as "what is the MVP that can run both websearch and gmail". As they gain customers, they gain features. (note: I used to work on Google App Engine [and Cloud])