Prime Instant Video is a Netflix-like streaming service that's included with an Amazon Prime membership. It offers unlimited streaming of more than 18,000 movies and TV episodes.

The service is separate from Amazon Instant Video, which rents and sells over 120,000 titles.

Amazon Prime costs $79 annually and offers free two-day shipping on Amazon purchases, as well as other benefits such as a free Kindle ebook rental each month. Kindle Fire customers get a free month of Prime service out of the box, and Amazon offers a to its other customers too.

The Amazon-Warner Bros. deal includes other TV shows too, including Dark Blue, Alcatraz, and The Whole Truth. (Don't get too excited.)

So what are Amazon's long-term plans for Prime Instant Video? Just last month, the online retailer announced a licensing pact with Metro-Goldwyn-Mayer Studios, bringing hundreds of classic MGM movies and TV shows to the streaming service.