Twenty percent of owners of high-definition television sets will only watch programs that are broadcast in HDTV, and 45 percent say they watch HDTV programs most of the time, according to a survey by Nielsen Media Research for the Cable & Telecommunications Association for Marketing. The survey also concluded that among those TV viewers who do not own HDTV sets 28 percent expressed interest in buying one; likewise 20 percent said they would be interested in subscribing to a digital cable system. In a separate study, Nielsen found that the average television viewer now spends 127.15 hours a month in front of a TV set -- up 4 percent from a year ago. "Timeshifted" watching now accounts for 5:50 hours of viewing per month, up 56 percent from last year. TV viewers now spend 2:19 hours watching video on the Internet and 3:15 hours watching it on their mobile phones.