Alright well, it's the Movie Store, and AppleInsider are porbably right about what they have said about it.
Meaning: Disney is the only one on board from the start.
However, don't **** your pants yet, that does not means we're stuck with Bambi and Mickey Mouse for 6 months.
The Walt Disney Company is about as expansive as they come, and they're particularly devious when it comes to branding. For various PR reasons they like to set up studios with different names and "tones" so that their cuddley flagship brand isn't trodden on by gritty adult movies.
If Disney are on board, that means as well as the "Walt Disney Pictures" movies like Toy Story and Aladin etc., Touchstone Pictures and Miramax are in (and also Hollywood Studios, but that's about to merge, it's not nothing notable since The 6th Sense, and nothing notable before that).
So you've got films like The Insider, Cinderella Man, The Royal Tenenbaums, Sin City, Gangs of New York, The Hours etc. etc. right off the bat.
Probably 1/5 of an average "movie fans" diet will consist of flicks produced by a branch of The Walt Disney Company, with another 5th being from WB, another from Universal and the rest from others like Sony and independants like Lions Gate and the Sundance groups.
You really wan't Universal in there eventually, as they're the ones with the big library. And Warner are the dudes holding all the old time classics, so you wan't them too.
Lions Gate make great films but the medium sized studios like them you can probably survive without, for the beginning, though it looks like Lions are in anyway.
Sony would be nice, they often hold the key to the films responsible for the recent surge in popularity of foreign films. Particuarly in Europe, Chinese and Spanish-speaking films have become really quite popular, with Zhang Yimou's Hero and House of Flying Daggers huge hits.
Of course, I'm hoping FilmFour get in their quickly, as they are responsible for really some of the most exciting cinema in recent years; Trainspotting, The Motorcycle Diaries, the list goes on...