Obviously, that's different today.
It's amazing to see the progress from anti-cloud (or private-cloud) to "we're cloud only" within that timeframe (I'm referring to companies that was hard-on on-premise).
AFAIK, SAP HANA is being used by NBA (NBA.com/Stats), NFL, NHL (http://www.nhl.com/ice/news.htm?id=754248) to provide real time statistics for the whole league. I wonder if they want to move their infrastructure to AWS.
PS: I work for SAP
My take is that people are doing it piecemeal. The datacenter guys got a mandate to make everything cloudy because of the obvious benefits (scale, provisioning time, lower TCO), but the data / application teams had already invested in something like HANA. If you can just forklift everything up to the cloud, there's at least the theory that you can start to peel off bits as they need to and integrate further with Amazon. If you're starting a streaming ingest process, it's appealing to forklift your existing batch ingest, then use Amazon's services to build the new one. Similar with DB upgrades (RDS), backups (S3 / glacier), or anything else that has a dedicated service. But the first thing to do is get the core application running so you're not trying to patch around some unholy hybrid cloud mess.