Research company SRG says that its most recent research confirms what is likely obvious to many observers – most young TV viewers are already living in a post-DVR world with much greater availability of online video both legally and also via peer-to-peer sources.

For the ‘Prime Time is Anytime‘ study, the company interviewed 1,200 Americans aged 12 and older in November 2008, during the fall sweeps and then compared results to past tracking surveys taken in the fall of 2007 and 2006.

Online viewing of TV shows at some point in the past is now at 50 per cent, double the rate of 25 per cent in the fall of 2006.

Hulu has significantly increased its awareness, with 24 per cent saying they have heard of the website. Hulu audience skews young and male - with an average age of 33 and 2-in-3 visitors are men.

15 per cent of online Americans have visited the website of one of the major networks in the last month specifically to watch a TV show online. But unlike Hulu’s audience, 54 per cent of this audience is female and the average age of 39 is much closer to the average of the broader Internet audience.

The research also found that online TV audiences are happier with their viewing experience compared to last year—46 per cent rate their latest viewing experience on one of the network sites as excellent, up 7-points from the 2007 average of 39 per cent.

Dancing with The Stars, Desperate Housewives, Grey’s Anatomy were among the top titles for online viewing on network sites.

Outside of YouTube, major of the top-of-mind destinations for videos, TV shows and movies are ABC, Yahoo!, NBC, Hulu, MySpace and CBS, each receiving over five per cent in mentions from online Americans.