Hi there,
The requirements are quite clear and straightforward to implement so no questions really. I'll use my own aws resources so no playground is needed. At the end of the job I'll deliver the source along with a screencast explaining each step needed for setup and running. If you prefer I can set things up myself on your playground as well.
By the way, I've worked on a similar project before which was also utilizing aws sns to receive updates about the transcoding progress. I can include that as well, in screencast at least, if you prefer.
I prefer python and it'll be ready in 2 days at most, thanks.