Season 4 isn't on DVD yet. Some people may not have seen it.
That's fair, though I think when you reach a point where 90% of the fanbase has caught up with a show and you're in that remaining 10%, it should really become your obligation to avoid spoilers and not someone else's obligation to shield them from you. If you're content to wait for DVD releases, you should probably also be content to deal with being spoiled by message board conversations and watercooler chat.
It's really only a hassle for something that is still ongoing like LOST. If the details of Season 4 have to be hidden behind spoiler tags then a lot of people won't read them because they'll think it's Season 5 spoilers. I suppose the situation could be remedied if people would just label things as "S4 Spoiler" or "S5 Spoiler", but that doesn't really happen. Even then it would be muddy, as there's probably a contingent of little bitches that would consider this relatively innocuous poster a Season 5 spoiler.
