From ArsTechnica’s article http://arst.ch/r4t:
Microsoft’s Windows Azure has beaten all competitors in a year’s worth of cloud speed tests, coming out ahead of Amazon EC2, Google App Engine, Rackspace and a dozen others.
The independent tests were conducted by application performance management vendor Compuware using its own testing tool CloudSleuth which debuted last year. Anyone can get results from the past 30 days for free by going to the CloudSleuth website, but this is the first time Compuware has released results for an entire 12-month period.
read the rest at http://arst.ch/r4t