Rhetroical question of course, because the answer is obviously No.
I just had a Movie spoiled for me because the Movie is so well-known that you would think the entire population of North America has already seen it. Even if that's the case... Even if 99% of North America has already seen that movie, there's still that 1% of the remainder of the population.
The same goes for popular TV Shows. I don't mind when they start off with something like "Next week on an All-New Lost...", but when they start the Promos with no warning like that whatsoever, giving you a shocking scene from next week's episode first, then saying that bit about "Next week on an all-new Lost".. That pisses me off.
This is what Spoiler tags are for people, this is why Network TV uses Warnings on TV Promos, and discussion threads on GameSpot or IGN keep theircomments tagged... So the rest of the World doesn't have to put up with the **** of having to hear it from someone else before they see it.