EC2 nodes are terribly underpowered, particularly in the I/O realm (the biggest weakness of virtually every site) where a standard desktop absolutely annihilate

EC2 nodes are terribly underpowered, particularly in the I/O realm (the biggest weakness of virtually every site) where a standard desktop absolutely annihilates the I/O performance of an S3 connection (where you have to perform software RAID to get anywhere near the performance of a single magnetic low-end SATA drive, which is absolutely terrible). A lot of the "web scale" noise has come from dealing with these gerbil sized instances.