Consumer information company Knowledge Networks released a study this week that examines how the U.S. TV-viewing audience consumes and interacts with offerings on TV networks’ websites, such as blogs, games, voting, podcasts, and, of course, video.

“How People Use TV’s Web Connections 2009” found that one in five (21%) Internet users ages 13 to 54 now accesses streaming video to watch full episodes of TV programs – up from 10% in 2006. Two-thirds (65%) of these “streamers” say they expect to be able to watch their favorite shows on “the device of my choice” – an expectation that reaches across generations, from 66% of teen “streamers” (ages 13 to 17) to 57% of those 50 to 54.

The Knowledge Networks report shows that, among streamers of TV network content in that 13-to-54 age group, use of third-party hosting sites (such as Hulu) to access TV network video content has doubled since 2007, from 14% to 28%. However, the networks’ own websites are still their most common source for watching network content.

Making full TV episodes available online also appears to create good will – toward networks and sponsors alike. 86% of age 13-to-54 streamers said they are “more engaged” with programs that they can watch on the Internet – up from 78% in 2006. And 66% said that having access to complete episodes increases their consideration of sponsoring brands, compared to 58% in 2006.”

Knowledge Networks’ report, “How People Use TV’s Web Connections 2009,” is now in its third year, detailing consumers’ changing use of and attitudes toward television network content on the Internet. The study was conducted among Internet users age 13 to 54. Over 1,900 persons were interviewed, including 1,700 broadband users.

In a related note about another fairly new technology, (see post from earlier today), another study, this one by the Pew Internet Project, found that 11% of online American adults said they used a service like Twitter or another service that allowed them to share updates about themselves or to see the updates of others.

With net TV watching at 21% vs microblogging 11%, does that mean that Twitter is only half as popular as Internet TV? (We’re only half-joking, here).