Does anyone run old world content anymore?

I remember fondly the first time my guild managed to take out Ragnaros in Molten Core. It had taken a lot of planning to make a serious attempt at it, and when everything finally came together just right it was a huge thrill. Or the first time we took out Nefarian in Blackwing Lair or Princess Huhurahn in Ahn'Qiraj or... any of a dozen other boss first kills. It may have taken countless frustrating wipes to learn the perfect strategy, but when things finally come together, it's a great feeling.

But does anyone go out and visit Ragnaros (or any of the other big boss mobs in Azeroth) anymore, when the loot's no longer compelling? I've got to say -- the people who started playing since the Burning Crusade was released are missing out on some incredibly fun boss fights. But I'm glad to see that there are at least some players out there who are tackling old world content for the entertainment value. Se7en Samurai points out that the guild Elements on Alleria is running an open Naxxramas raid this weekend. (If only guilds on my realm did things like that!)

So what's your take on it? Is old world content worth going through for entertainment value, or is it all just a waste of time?