Even as AMC was still airing the startling third-season finale of its addictive drama "Mad Men," bloggers and fans began reveling in the episode's revelations. In the age of DVRs, when so many viewers watch the show days later, should the TV community shut up until others get around to watching Don Draper tell Betty that...oops, sorry.

Once a show has aired, it's fair game:
"I'm personally against spoilers," says Jace Lacob in Televisionary, because they ruin the surprise for everybody. But I was "rankled" when a reader berated me for failing to post a "spoiler alert" on an interview with "Mad Men" creator Matthew Weiner I published after the show's finale.
"Spoil-sport: Why talking about an episode that's already aired isn't a 'spoiler'"

Failing to post a "spoiler alert" is lazy and rude: Writers should respect their readers' watching habits, says David Chen in SlashFilm. We're "rapidly moving away from the idea of fixed schedules for television shows." How hard is it "to just throw up a sentence" warning readers that you're about to spill the beans?
"Spoiler alert: The responsibility of online writers in a Hulu/DVR world"

Yes, it's polite, but there's limit: Some "spoilerphobes" go overboard and request spoiler alerts for everything, says Linda Holmes on NPR's Monkey See blog. Sympathetic writers try to play along, and some won't discuss big plot points until a day or two after a show has aired. But here's some common sense: Don't read a post "about Mad Men the morning after the finale that is clearly about the finale if you haven't seen the finale."
"The spoiler problem (contains spoilers)"