Within 5 years all new laptops will have touchscreens. Many desktops will come with LCD touchscreen monitors but not as many as laptops. Windows 7 has already announced support for touch interfaces. Apple has a library of touch controls and gestures that it will bring to the Mac from the iPhone soon.

Last night I was reading an RSS feed that had an embedded video. Right in the middle of the video was a giant "play" button. My first reaction was to reach out and touch my laptop screen just like I would touch the play button on my iPhone. Once you've used a touch interface you realize how much you miss it when it's gone. 

The mouse isn't going away anytime soon. Holding your hands/arms up to the screen like Tom Cruise in Minority Report isn't very comfortable. We'll see a mixutre where mouse and keyboard continue to rule but touch screen interfaces are available for those tasks that make sense. Painting, organizing, scrolling and zooming can be much easier and faster with fingers.

If you're a web or application designer the Web 2.0 trend of large fonts and brightly colored buttons will be extended to larger more "finger friendly" buttons. If you're designing a new site remember that larger "click targets" will be needed for touch interfaces. The great news is that adding larger buttons and click targets will make your site more user friendly today for mouse users. Many usability studies have shown that the four corners of the screen are the easiest and quickest locations for users to click with a mouse. The larger the area the user has to click (even when it's not a corner) the better. Nothing is more frustrating that seeing a link you want to click but it's so small that you can't get your cursor on the exact right pixel. 

Start getting ready for touch interfaces today. Use larger buttons, make sure click targets around links are large and try not to group buttons and links so close that a single finger can touch both at the same time.