Here's the data point I found most interesting:
I have followed many cloud surveys and reports that measure cloud traction of the different providers (see for example Guy Rosen's State of the Cloud). It has consistently been the case that Amazon is ranked #1 and Rackspace #2 (which is what prompted my Rackspace: The Avis of Cloud Computing post). The Zenoss survey suggests a different story with Google App Engine and Microsoft Azure coming in at #2 and #3 respectively, pushing Rackspace to #4.
Also, GoGrid's penetration, as well as RightScale's (which is a very different animal than the other players on the list) is very impressive.
Note that the wording of the question in the survey was a bit ambiguous: "What are your cloud computing plans for 2010?". I say ambiguous because the survey was conducted Q2 2010, so probably close to the middle of the year. But in any case, it has a forward looking element to it, which gives a little indication of the trends as they are happening.
Anyway, lots of interesting info on both cloud and virtualization. Check out the full survey results (requires registration).