Its a bit of an open ended question so feel free to be as creative as you like with the answer.
The fact that millions of farmers in China can access most of human knowledge with devices they carry in their pockets ...
It's not just Chinese farmers. There are now tens and soon hundreds of millions of people walking around with most of human knowledge available at their fingertips.
The next big thing will be what enables them to make use of that information.
The next big thing in tech (by which I mean PC big, Internet big or Windows big) will be bio-integration, by which I mean interfaces that interact with or augment biological functions.
The hacks we're seeing on Kinect will eventually filter into products. We've already seen circuits implanted on contact lenses. We're already seeing augmented reality on phones becoming normal.
Now, imagine glasses that project displays Layar style several feet in front of you. Imagine contact lenses that do this, or that change shape depending on where you're looking and how you're focusing.
We already have prototypes of these things, or are part-way along the way to achieving them within the next 5-20 years.
Now imagine map systems that talk to a wristwatch that 'pulls' north or towards your route so you don't need to use a screen to orient your surroundings. Imagine walking into a room and closing the curtains with a gesture. Turn the volume up and down like a conductor.
Those last ones are possible with current technology, they just need to find their way into commercial products.
So you're meeting a friend at a cafe and you're running late. They can see a pointer to where you are, and their contact lenses are automatically notified of where you are 5 minutes before you're meant to meet them (through notifo 8.0, natch). It's ok though because your coffee order was put through and they know not to begin to fulfil your order until you get within 100m of the café. Your friend gets notified of the great Vancouver coffee riot (due to crop failures there's no coffee in Vancouver, the withdrawal was a powder keg waiting to explode) as they followed the hashtag, articles from the New York Post mingle with tweets in a semi-transparent newspaper style display about 3 feet from them, but your friend likes old fashioned themes. They get pinged automatically once you're about to come around the corner (thanks to a YC funded Google Maps/Notifo mashup) just in time for your coffee.
We have the tech for almost all of that already, the main issues are bandwidth, integration and battery power, and the lenses.
Now Imagine a wrist-based device that monitors your heart beat by collecting data from sensors on your chest, can work out your blood sugar level from the flow of magnetically charged sugar-bound nano particles and that can administer insulin through a peripheral catheter.
Bizarrely, we have the sensors, we have the potential to create the nanoparticles within the next 5-20 years, the only issue is the administration (currently it would be a catheter or subcutaneous administration for some, but alternatives are in the works). With that technology we could use it to administer all kinds of stuff.
Now imagine all of that combined with the ability to interact with people both near you and on the other side of the world with no difference, save some lag.
You could be sat there in the US, having your meds and numbers monitored remotely from Manilla by trained staff, and your meds will administer once it notices a significant adverse change. You could then blink, then look towards the menu item you want to bring up and see your granddaughter's school recital in Paris streamed over the Internet and watch it as though you're there (or rather you could if Flash wasn't such a hog and your glasses kept stuttering, maybe time for an upgrade to iGlasses 2?) and not miss the 49ers game.
That's where I think we're headed. I think that will be the biggest thing in tech until we're replacing organs cloned from the patient's own cells and can grow blood in a machine.
Anyway, that's just my 2p worth (perhaps 20p then!). what does everyone else think, am I nuts?