I wonder how long before they no longer feel the need to give us the illusion of freedom?
They'll keep it up as long as they can. Maintaining control through propaganda is preferable to maintaining it by force. It's cheaper and more stable. Most people still buy what they hear on the news. Even though people are starting to chafe under the surveillance, most still think it's about terrorism (as opposed to maintaining the status quo). If the powers that be do have to resort to jackboots in the streets, the media will make sure to characterize it in the right way. Again, most people will buy it.
Like they say in the movie, most people are not ready to be unplugged from the matrix. It would take something supremely radical for them to start distrusting the news and make a real break from the world view that they have. Most will never do it. We all know how people will generally continue to believe what they have always believed, even in the face of contrary evidence. At this point the illusion is so pervasive people will maintain it themselves, without help, because they firmly believe the illusion is real.