Back in 2006 we covered the launch of the Amazon Unbox video service which was then being pitched as the best alternative to the iTunes Store. There was one big problem: it didn't support Macs. Now, finally, Amazon is starting to rectify the situation with their new Amazon Video on Demand Service. PC Magazine has a First Look at the Service and, sure enough, it now supports Macs.
It appears that the new service will be similar to Netflix's streaming (which does not support the Mac, though they have promised it a long time ago) in that you'll be able to watch 40,000 movies and television shows in your browser. Unlike Netflix, however, the content will be priced individually with no subscription options. The video will be streamed with Flash 9.
Unfortunately, the program is still in beta and Amazon apparently has enough testers at the moment. However, you can sign up for their beta mailing list if you want to get in the next time they issue invitations.