In an On Demand binge I caught up on the last couple of weeks of Eureka &and felt pummeled by promos for NBC's The Event. Because the NBCU shows only currently run one ad during On Demand breaks and they are pretty short, I find it's not worth the trouble to fast-forward them and typically just grab the iPhone to check e-mail. But, by about the fourth time I got hit with one of the promos for The Event, I was hitting the mute button because it had become like nails on the chalkboard.
Nonetheless, I consider the promotion effective, at least for me. I am quite aware of the show (and that "We may have a problem. He's going to tell them about the event.") and if nothing else, I find it hard to imagine the actual show could be anywhere near as annoying as the promos. Play these three times each and see if you can make it through a fourth.