You know what they say: "Bigger is better." That's why the average screen size for most devices has only been rising the past few years or so. Devices such as desktop monitors, televisions, smartphones, GPS devices, and even portable media players have seen a rise in the average screen size, but laptops sadly don't share the same statistic.
A study from NPD DisplaySearch shows that the diagonal length of displays on electronic devices and even public signboards is increasing. Smartphones, specifically, will see a whopping 38% increase in screen size by 2013 based on data that dates back to 2010. This isn't too surprising, since the popularity of 5-inch "phablets" is rising fairly quickly.
OLED televisions will see a 267% increase from 2010 to 2013, with the average screen size jumping from 15 inches to a massive 55 inches. Despite the significant jump, this also isn't too surprising, since OLED technology is still rather new. However, one category that hasn't seen a rise in average screen size are "mobile PCs," which consist of laptops, netbooks, Ultrabooks, and tablets.
While that may seem like a surprise, the popularity of smaller form-factor laptops and Ultrabooks has made it so that the screen size usually doesn't go over 15 inches, and it most likely won't for some time. It's the same deal with tablets; anything over 10 inches is considered fairly large and bulky for a tablet.