Internet services are becoming critical to the future of television as TV manufacturers in 2011 aim to  ship more than a quarter of all flat panel TVs with some form of Internet connectivity.

According to market research firm  DisplaySearch, this number is forecast to grow to 138M units in 2015, accounting for 47 percent of all flat panel TVs shipped.

"The adoption of connected TV is not just taking place in developed regions," said Paul Gray, DisplaySearch Director of TV Electronics Research, in a statement. "Emerging markets often have good broadband services, and there is a thirst from consumers to get the best content available."

According to DisplaySearch research, by the end of 2015, over 500 million connected TVs will have shipped.

The recent decision by the Indian government to switch off analog terrestrial signals and move to DVB-T2 digital broadcast in 2015 paves the way for further innovation and brings forward the possibility of a major new market for connected TVs, according to the report. At the same time, trends like WiFi Direct enable the television to hook up more readily with handheld devices in the home, such as smart phones and tablets.

DisplaySearch forecasts that more than 98 million TV sets with 802.11 wireless networking built-in will ship in 2015.

"We expect that in 2015, 35 percent of 46-in or larger TVs in North America will be smart TVs, defined as having the following capabilities: able to retrieve content from the internet without the restrictions of a portal; intelligent search and recommendations; upgradeable by its owner; and able to network seamlessly with other devices in the home," according to Gray.

The findings are available in DisplaySearch’s Q2’11 Quarterly TV Design and Features Report.