1) Cell phones could already be used for texting or anything else that is 100% text in a movie theater, very easily. Either have the screen be mostly back with the words be a darker color than white (yellow is a good color for this). The amount of light coming out, in that case is very minimal and would not disturb others around you, as long as the phone is kept low. Also, something like google glasses could take care of it.
2) No, the future of movies is not "wear more/different crap to make movies magically change!" No one wants to wear stuff. You know what happens if the choices are, "pay more asshole, or get blasted with ads all over the place"? More people stay home, wait for a home release, or just pirate the movie. This is what happens when you antagonize your audience. See: video games.
3) You're right about streaming/digital distribution of movies changing things, drastically. When it comes to the end-user (read: us), it's really not going to be much different, unfortunately. Yes, we might have some more niche/oddball choices here and there, but the savings of not distributing movies will not be passed onto us and as much as a world where a film could be "fixed" while in the theaters sounds cool, it won't happen. There's no real money in it.
Honestly, what's going to change most in going to the movies is what's offered. It's not the 1950's, people don't need to go to the theater to see something, there are MANY other options. Going to the movies is expensive and compared to home, it's not a great experience. Offer more. Better seats. Better/more reasonable priced concessions. A better guarantee of silence and not having my seat kicked by the brat behind me. Then, and only then, will stacking things like "pop-up video," rifftrax, and other fun stuff will make me care.