Personally, I'm the exact opposite of the people Yahtzee asked as far as raiding goes. I don't raid to get items, I get items so that I can raid. Raiding is just enjoyable to me, as raid bosses frequently have the most complex and interesting mechanics in the game, and usually requires a bit more paying attention than the rest, plus it gives me something to do with my friends that also play. Personally, I really couldn't give a shit what my numbers look like so long as they're good enough to get the job done and I'm not holding other people in my raid group back, so I do have to get more items, if only to keep pace with everyone else, but if raid bosses suddenly stopped dropping loot entirely I would still do them. Once I've done all of the raids is usually the point in the game where I become bored and want to go and play something else, as to me, beating all the raids is the equivalent to beating the game.
Though I fully realize I'm probably in the minority as far as this opinion is concerned. Hell, I'm one of those rare people who actually enjoys levelling, whereas everyone else I've ever spoken to hates it with a passion.