I speculated a year and half ago that AWS would add SSD, but I was wrong and AWS added HPC instead.
GigaOm reports on CloudSigma adding SSD support.
CloudSigma adds SSDs to its public cloud
There is mention of the lower power consumption, but the key is performance. BTW, part of why I like my MacBook Air is its 256GB SSD that makes my machine outperform my other laptops.
The SSD is meant for high performance areas of the cloud.
At this point, CloudSigma is targeting its flash offering at tiered storage environments in which companies place “hot” data or data that requires high I/O throughput on flash, while keeping less-performance-intensive data and backup operations on hard disks.