Nielsen, the leading television rating company, will start tracking DVR use and adding it to its ratings reports, which will now come in three forms.

Responding to the requests of clients who wanted to know how DVR use affected viewing, Nielsen will now offer three ratings per program and network: Live, Live/Same Day (which includes same-day playback via DVR) and Live 7 Day Ratings (live along with time-shifted viewing up to 168 hours after
airing).

Video by iPod gains momentum.