Amazon has announced the new Access Logs feature for CloudFront streaming distributions. With access logging turned on you can see when and how people interact with your streamed content.
The latest JetS3t code provides basic API support for enabling and managing these access logs, in much the same way as you do for non-streaming distributions. See the recent changes to the CloudFrontSamples.java file for example usage.
Note that this new feature has not yet been widely tested so file a bug report to let me know if you have problems.