If the latest rumors are to be believed, apparently Netflix might just be offering up movie streaming for subscribers on their iPhones and iPod touch devices. And while nothing has been confirmed yet, it does seem somewhat likely.
The "Watch Instantly" feature will supposedly soon be available on Apple devices as well. You would only be able to access movies if you had a Wi-Fi connection, not just 3G.
We don't know at this point if a special app will be required to watch the movies, but since the iPhone doesn't have Silverlight or Flash support, it would need to use the video streaming built-in to the devices. None of this is official yet, but since Netflix is continuously expanding their availability, this move would make sense.