According to Nielsen, 40% of smartphone and tablet users are so fascinated with using those new devices while watching TV -- to check emails, send social messages or go to websites -- that TV programs could be suffering. Much has been made about social media helping TV shows. But maybe it doesn’t help the likes of "Modern Family," "The Vampire Diaries" or "The Walking Dead." Sixty percent of people with mobile devices surveyed said they checked email while watching TV, while 40% to 50% engaged in searches unrelated to the shows they were watching. All of which means that fewer people are engaged in the stuff on the big TV screen -- not only with the programs they are supposedly watching but with the commercials. Critics of Nielsen, of course, always say that ratings can be a measurement more of "tuning" than of actual "viewing." What to do? Make commercials and programs quicker -- with better dramatic plot-lines in dramas, better comedy content in terms of jokes, and of course, more entertaining reality on reality shows. What is really valuable here? TV entropy, I'm guessing. TV engagement is still a useful value -- if you can find it to any meaningful degree. But perhaps marketers should place a value on the flip-side of engagement -- distraction -- to figure out what they are missing. It turns out that TV networks this season have been doing their own multitasking -- trying to hold down the fort on still-sinking ratings of existing shows while quickly cutting the deadwood of new stuff. It’s not even a month into the new season and four shows have already been canceled, with a bunch near the edge. The list is made up of ABC's "Charlie's Angels," NBC's "Free Agents" and "The Playboy Club," and CW's "H8R.” A fifth show, CBS "How to be a Gentlemen," is on life support, having been moved to TV Siberia -- Saturday night. What could research on media multitasking have told us about these specific shows?