Probably a topic for a different thread, but Ultraviolet seems (to me, at least) the best option for the long-term viability of movie DRM. Major film studios such as Sony Pictures Entertainment, Universal Studios, Paramount, Warner Bros., and Fox are on board as well as DreamWorks, Lionsgate, Roadshow Entertainment, BBC, and HBO. VUDU (currently the largest and most popular Ultraviolet provider) is owned by Wal-Mart (which isn't going anywhere any time soon). FandangoNow and Flixster (both owned by Fandango) also seems like it'll be here to stay. Verizon Fios supports it. We're also nearly 6 years into the lifespan of the system, and we've seen it grow from supporting SD and HD content to now include 3D and 4K (UHD) content so it seems pretty agile.
Obviously, everyone is free to choose the platform that fits their needs the best, but as someone who cut the cord years ago and exclusively streams my TV and movies, Ultraviolet is my movie library platform of choice.