Market research group the NPD Group this week released a report showing that Americans now view more streaming web content through their TVs than on their computer monitors.

NPD’s “Digital Video Outlook” report shows that 45% of Americans now primarily stream their video through their TV, up from 33% one year ago. At the same time, Americans who used their PC as their primary streaming video viewing platform decreased from 48% to 31%.

These results undoubtedly point to a wider adoption of internet-connected media devices such as Roku boxes, video game consoles, and internet-connected TVs. NPD estimates that 10% of U.S. households currently own at least one “connected” TV.

“The growth in connected TVs is another sign that online video is maturing,” said Russ Crupnick, senior vice president of industry analysis for The NPD Group. “Streaming video has moved from the dorm room to the living room; and, as more households obtain and connect TVs to the Web, we predict increased trial and engagement for video distribution services.”

It’s another certainty that Americans aren’t just watching YouTube videos on their TVs. NPD’s report shows that Netflix Watch Instantly is used by 40% of those who have internet-connected TVs. Also, 12% of internet-connected TV viewers use HuluPlus to stream content, and 4% use Vudu.

Interestingly, NPD also found that 1/5 of Americans who obtained a “connected” TV no longer used peripheral devices, such as streaming video boxes or video game consoles, to stream content. Not surprisingly, it seems U.S. consumers might actually want an all-in-one solution for their home entertainment needs. If cable companies would play ball with Apple and get in on an Apple HDTV, they might stop ceding ground in the streaming video market to Netflix.