CloudHarmony has long been benchmarking cloud computing platforms and publishing their results on Phoronix Global (see their public test results), but now they have published an incredible number of tests from many different cloud platforms and configurations. Also on their blog is an extensive analysis of their test results.
Using a number of the different Phoronix Test Suite tests they also end up defining a new cloud computing performance unit: a CCU, or CloudHarmony Compute Unit. Among the cloud providers benchmarked were Amazon EC2, Rackspace Cloud, Storm on Demand, GoGrid, Voxel, NewServers, Linode, SoftLayer, Terremark vCloud Express, OpSource Cloud, Speedyrails, Zerigo, ReliaCloud, IBM Development & Test Cloud, BlueLock, Cloud Central, RimuHosting, ElasticHosts, and Flexiscale. Had it not been for the Phoronix Test Suite and its automated test installation and execution, this cloud benchmarking would have taken an extremely long amount of time.
Read this blog post for their analysis of different cloud providers and their results from the 150 different cloud server configurations with 20 different vendors.