i get pissed when i miss any of the previews before a movie starts in a movie theater. on the other hand, i don't seek trailers out online (e.g., new star wars teaser today). i figure i'll see them when or if i see them on the big screen or tv. finally, if i am watching a dvd or blu-ray of a film i've never seen, i always watch any trailers for it after the movie. usually i recognize immediately how much of the movie would've been given away. that isn't a new phenomenon, but it is pretty annoying. i avoid them in this case because i already missed the original theatrical run (sometimes before birth), but seeing a trailer for an upcoming or current film can be very influential on when or if i see it.