The Redbox is doing fine right now but I see it as something that will be obsolete very soon. I only see them in budget shopping areas, probably marketing to people who don't own computers or have Internet at home. People who can't use Netflix or people who have not yet embraced online shopping. Those people are a rapidly shrinking demographic. I am not sure if the Redbox is an individual franchise like a soda machine or not so I don't know what selection is like everywhere, but the ones I have seen are easel 2/3 b-movie straight to video stuff nobody has ever heard about. The selection of actual Hollywood hits is pretty slim. I have never even considered using one. If I see a movie I like that is not already queued up in Netflix I just snap a photo and go home and add it. I also do not know how many copies of a movie these things can hold so I don't know what the odds are of one being rented out but it's at least possible at some degree.
I do think streaming media everywhere, not just Netflix, is the future. I don't think it's going to happen overnight though. Disc rentals still have at least a few years left in them.