Flixster is an app in which movies can be purchased and downloaded to your idevice. The same can be done with Flixster Collections on your MacBook or iMac.
According to Flixster's support pages, the current app can be used to download the movie for later viewing or to stream the movie with a wifi or 3g connection. Since I've recently downgraded my data package from unlimited to 200mb/month, this isn't an option.
Here's the fun part; in order to delete the movie from your idevice, you must uninstall the app. In-app deletion is a forthcoming feature with Flixster. However, if you wish to rewatch the movie at a later time, it must be downloaded again through the Flixster app after re-installation. Keep in mind that you're allowed to download a movie title only five times with the redemption code that came with your blu-ray/dvd/uv combo pack. Since DH2 was released at midnight, I've already downloaed the movie twice since the first copy was corrupted and wouldn't play in Flixster Collections on my MacBook.
So far, I've not been able to find a way or get a definitive answer from Flixster (1-415-255-7215) or Warner Brothers (1-818-954-6000) on how to import the digital copy into my iTunes library, which may not even be possible (through legitimate means).
Yet.