I didn’t see these details elsewhere, but Comptuerworld reports:
Initially ESRI will offer ArcGIS Server Enterprise Advanced v10, along with a few extensions, on AWS. “The ArcGIS Server Amazon Machine Images, hosted in the AWS cloud, will not be made available until the ArcGIS Server v10 release [in July], and only for customers under an ESRI Enterprise License Agreement,” says Victoria Kouyoumjian, IT Strategy Architect at ESRI. Users who don’t want to wait for the release of v10 can run ArcGIS Server 9.3.1 in the cloud, but that requires retaining ESRI Professional Services to assist in getting it up and running.
