I wouldn't have minded winning the mount myself, but for me the joy was mainly in redemption. Two Mondays ago, we had been in a total groove and arrived at the final group of mobs to kill before the last boss and I screwed up and aggroed the boss and the mobs. We wiped and missed the prize by a minute. Being near-perfect for 44 and a half minutes just won't do.
But last night we did it. I hadn't actually screamed "f**k, yeah!" out loud on a kill in a long time before last night. My 14yo daughter head me and thinks I'm nuts. I guess that's not news. It does mean we were able to accomplish something that not every group of players in World of Warcraft can get to. Acknowledging this, Blizzard has indicated they are taking the ability to get the mount out of the game in the next expansion in order to preserve it's pride status as having been accomplished when it was hard.
Succeeding in this run requires 10 people staying in complete sync for 45 straight minutes. Tanks tank. Healers heal. Dps does damage. And no mistakes. No overpulling, no healing gaps on the tanks, no aggro pulls of the mobs off the tanks. The overall level of dps has to be very high to maintain the speed. We learned that trying to shave the 14m off our early attempts. Everybody needs to know the whole route and the special abilities of the four bosses and most importantly, how to work together as a team.
You also can't really do this in an egalitarian way. You need people with lots of experience and really good gear from other raids. It was tough turning away people who wanted to come try the run with us (and we'll be working on getting more people into the run now that we've got it down). But it's hard. And that's why meeting the challenge is so rewarding.
People raid for a lot of reasons. Most of them are based on the feeling of pushing yourself and your team and meeting terrific challenges. Plus sometimes, you get a little something to show off for your success.