- Steve McClellan

NEW YORK With U.S. digital video recorder household penetration nearing 28 percent, the devices are having a greater impact on prime-time ratings than videocassette recorders, even when that technology was present in 90 percent of the nation's homes.

In the first four weeks of the new TV season, DVR time shifting accounted for 11 percent of all prime-time ratings on the five broadcast networks, according to new research by IPG's Magna.

What's more, DVR playbacks now equal 16 percent of all prime-time viewing by consumers age 18-49, per Magna. That's more than double the impact VCRs had at the 90-percent penetration level.

In DVR-only homes, nearly 40 percent of household prime-time viewing (and 50 percent of prime-time viewing in the 18-49 age range) is now time shifted, according to Magna.

The research also indicates that program genre, not size of audience, is a better barometer for likely DVR playback. Action, sci-fi, medical shows and serialized dramas all tend to have above average DVR playback. Comedies, with the exception of NBC's The Office, tend to fall into the average range of 5-20 percent, per Magna.

The Office had the highest level of playback with 28 percent of the show's total audience watching in time-shifted mode. Rounding out the top five most played back shows: Heroes (27 percent); 90210 (26 percent); Fringe (25 percent); and Terminator: The Sarah Connor Chronicles (22 percent).

Magna said young adult viewers time shift more often than older viewers. So far this season 31 percent of the time-shift audience falls into the 18-34 age range, while adults 65-plus account for just 6 percent. For live viewing, those percentages are 18 percent (for 18-34) and 20 percent (65-plus).