Because the volume of tweets about Lost when it airs is so high that it trumps everything else. Here is perhaps a better example: http://twist.flaptor.com/freq

Because the volume of tweets about Lost when it airs is so high that it trumps everything else. Here is perhaps a better example: http://twist.flaptor.com/freq?gram=american&table=0 http://twist.flaptor.com/freq?gram=american&table=0 If you click on the peaks (caused by American Idol) you'll see the results for a query on the term "American" at that time. A significant number of those mention American Idol. Now click near the right of the chart. Almost no results mention the show.