It's not live yet, and you have to register to see the beta when it comes - but it looks interesting.
Take a look at the FAQ. Looks interesting. Note the following points (taken from the FAQ):
- Benefit: Scale, with virtually no restriction on storage
- Target Customers: Running applications that have limited or batched data access.
- Typical scenarios include business solutions like HR services, healthcare records management, data archiving and internet facing applications like social networking and picture sharing.
- The SQL Server Data Storage Service can store multiple types of data, from birth to archival. Users can upload and query structured data, semi-structured data, stored in flexible entities, and unstructured data. Customers will be able to associate entities with large unstructured data objects (blobs) which could be accessed as URL addressable resources.
- Data is stored in large storage clusters in various Microsoft data centers located across North America. We are planning to offer the service from international locations such as Europe and Asia. Users can group their data into authorities, which are affiliated with specific data centers and therefore provide control over the geographic location of the data.
- Easy access with REST and SOAP protocols