With all this 'lip dubbing,' are you paying attention?

Get ready, advertisers, because an impression is no longer an impression.

Our story begins with two tactical news items. Amazon.com has announced it will allow visitors at its movie site imdb.com to watch movies, trailers and TV shows for free with limited commercial interruptions, often before the TV shows air on broadcast television. And the ad blog Herd notes that Vimeo, the video-sharing site with crisper resolution than YouTube, continues to grow with user-generated content such as its popular "lip dubbing" contest.

All of this creates an issue much deeper than the cannibalization of viewers from traditional broadcast -- we call it the fallacy of impressions. Today's media consumers are multitasking: Twittering while they watch CNN, downloading music while they send emails, watching James Bond in Casino Royale in a small browser window while they work. (Whoops. That last one is us.)

In simple terms, this means 1,000 "impressions" -- the currency of impact bought by advertisers -- may be only 200 or 300. As users consume media in multiple formats at the same time, advertising impressions become something less than a true imprint. The calculation of GRPs and CPMs is hazier if the viewer who ends up exposed to your ad is partially checked out, playing chess or sending instant messages at the same time the ad rolls across the screen.

A while back MRI conducted a study that ranked different media by how attentive consumers where at different times of the day to each media option. The results weren't pretty. In the morning, for example, only 31.4% of television viewers said they were "very focused" on the TV, which means about two-thirds of all ads broadcast in that period may not be noticed.

Expect the tune-out to continue. The solution? Media plans will soon need to estimate the attentiveness of your audience in addition to how many impressions are made.

Lip dub by Leonardo Dalessandri.