21 percent of all TVs shipped in 2010 had Internet connectivity. The total this year was fueled by high penetration rates in Japan, according to the research firm DisplaySearch, which expects emerging markets to play a key role in the category. Units in Eastern Europe alone are expected to quadruple from 2.5 million in 2010 to more than 10 million in 2014.

DisplaySearch forecasted that about 45 million units in 2010 had Internet connectivity, 63 million units will be sold in 2011, 87 million units in 2012, 104 million units in 2013, and 122 million units in 2014. Here's how DisplaySearch defines what constitutes a smart TV:

  • A TV capable of upgrades and changes to functionality, typically by loading apps.
  • An ability to receive content from the open Internet, not just a walled garden.
  • Inclusion of an advanced user interface or content discovery engine, but not a standard browser with typed search terms like a PC.
  • An ability to communicate with other networked devices in the home via open standards.

"The looming risk now is what happens if every connected TV gets used," Paul Gray, director of European TV research with DisplaySearch, said in a statement. "With Netflix accounting for 20 percent of peak internet traffic in the U.S., it's reasonable to ask if the infrastructure can cope. Set makers need to understand that broadband access does not scale endlessly like broadcast reception."