I keep hearing that more and more people are watching movies and TV shows on their iPads or other tablets. That's amazing; every single one of these folks probably owns a large flat-screen display, but the "convenience" of watching a tablet in bed or on the train is a better fit. It's a lifestyle issue, where size really does matter.
Sure, they haven't completely stopped watching their 50-inch displays just yet, but give it another five years and I guarantee some of them won't be replacing their old sets when they break. The people who buy big displays for their kids to watch "The Lion King" umpteen times will start to realize the little ones would be just as happy watching it on a tablet they could hold in their hands. By 2020 younger people who will have grown up with tablets won't see a need to ever buy a big display, which will by then seem as obtrusive as a pair of 4-foot-tall tower speakers do to most buyers nowadays.
Yes, I know some of you are thinking that's impossible, people will always want to watch stuff on a big display, and I felt the same way about music 20 years ago, "Sure, technologies will change, but people will always want to listen to music over a set of good-quality speakers," but they don't. Large home theater speakers, even ones that fit within the budget are rarely considered. With music, everyone except for a handful of audiophiles, listens in their cars, computer, or on iPod. A home hi-fi of any quality now seems irrelevant; the same fate is in the cards for TVs. They will start to look too big, too imposing for the room's decor.
I'm not claiming sales of big-screen displays will go to zero, just as sales of big speakers haven't completely gone away. There will always be a market for big TVs, just as there is for great audio, but big-screen sales will continue to shrink over time. Most people will be perfectly content to watch movies and sports on their iPads. After all, when you're sitting up close to an iPad the picture can take up a large part of your field of vision. Plug in a decent set of headphones, and the sound will be fine. Ditching the big display that's hogging too much real estate in your living room will start to seem like a great idea.