At the end of the first quarter of 2012, there were 905 billion objects in Amazon S3. We routinely handle 650,000 requests per second for those objects with occasional peaks substantially above that number. Here is the latest chart:

The S3 object count continued to grow at a rapid clip even after we added object expiration and multi-object deletion at the end of the year. Every day, well over a billion objects are added via the S3 APIs, AWS Import/Export, the AWS Storage Gateway, all sorts of backup tools, and through Direct Connect pipes.

— Jeff;