I've been on a bit of a CyberPunk kick lately. It started with my picking up the Android Netrunner card game, and got me reading Snow Crash by Neal Stephenson. The book has a character that it describes as a Gargoyle. It's someone who walks around with a computer strapped to himself with googles on as a heads up display, and can be on the internet anywhere he goes.
Now, the book doesn't say exactly what year it takes place in, but I'm guessing that we're about there. Really, I think most of us (or at least those of us with smartphones) are modern day gargoyles. We are connected anywhere we go. The problem that I see, is that it doesn't really take Moore's Law into effect.
Moore's Law states that transistor size will reduce by half every 2 years. So, if you're trying to envision what technology would look like 20 years from today, you have to think of our current top technology, and shrink it in size 10 times. Exponentially speaking that means something with the computing power of an iPhone would be 1/1024th the size of a current iPhone. That would be about a tenth of a millimeter across.
Eventually Moore's Law will break down, but that's when we get to the atomic level.
So, anyway, if you're writing some sci fi, you might put some thought into how quickly technology is going to evolve.