The online service is similar to the company's movie download facility. But as it is streamed, you don't have to wait for the movie - no downloading means no download time.
If you have a Sony Bravia TV complete with Bravia Video Link, then you don't even need a PC to watch any movies you purchase on VOD (video on demand).
This bypassing of computers and set-top boxes is something that Sony has had in the pipeline for a while.
So far every major studio has signed up to Amazon Video On Demand, with only Disney and ABC not following suit, due to their partnership with the Apple Video Store.
At the moment, the service is only available for the US and considering the UK has only just been given access to Amazon's MP3 download service, expect a rather lengthy wait.