What's funny too is that we've become such a massive spoiler and instant gratification culture, that if someone is out of the loop long enough, everyone else gets fed up by them too.
How about sport events? I'd say those have a half-life of about a day. If someone misses the big game live but has it recorded, I think it's only about a day before the world moves on to talking about it. Imagine how frustrating it would be to be hanging with a group of friends, talking about soccer and one friend says, "Wait! I haven't seen the matches from the end of last season! Don't tell me who won the league yet."
Take care all.