In my opinion, we will not be seeing hovercars, mediclothing or holigrams in fifty years. We might have the technology to make some of these things in fifty years, but in reality a lot of people won't accept this technology.
Flying cars, it is hard enough to get a toyota prius off the dealership. If there ever is some easy to use hovercars, it would take at least 20 years to get the old cars out, provided all the car companies stop selling ground vehicles, which is also pretty unlikely.
Medical sensing clothing:
Other then the obvious downside of having to wear clothing
... The sensing clothing just isn't a good idea. You need it to look good so people will buy it, you need small light computers to actually do what you are advertizing (which requires pretty large equipment that directly attaches to the body) They also need to make it comfortable and the equipment needs to be washer safe and still cheap enough for people to buy.
Holigrams:
People still use those ancient CRT monitors, My tv is a CRT Television. Most people don't have HDTVs, Most people only use one monitor per computer. Our society is not ready for a holographic image in front of us, for now, the best thing for TV companies is to make really big affordable Plasmas and HDTVs.
