I read a post over on Tobold's Blog where he stated that he doesn't find a challenge in grinding out rep or other repetative tasks. As I have been spending a good deal of time doing this very thing, it got me thinking what do I find the most challenging about what I'm doing in the game? I have mentioned that I'm currently grinding Netherwing rep for the Netherdrakes (I should be at exalted with them by Saturday) and I am also in the process of grinding Sha'tari Skyguard, Mag'har and Horde faction rep to get the 50 mounts achievement with the albino drake. I've also started running old world and Outland dungeons to get the achievements there.
Now, grinding rep is not really a challenge, per se, as much as it is an endurance trial. Do you have the time and patients to do the same set of quests over and over every day for a few weeks (or in some cases, months)? Before there was such a thing as achievements, the answer for me was that I most certainly did not. I ended up getting exalted with the Skyguard on my Warlock mainly because I needed the money to buy an epic flyer for him. I got halfway through exalted with Netherwing as well before I gave up to level another alt. But with achievements thrown into the mix, there's another reason to spend all the time. Before, you would get a drake for completing the netherwing quests day after day, now I'm going to get six drakes because I (1) have money to blow on things that don't matter (helloooo mechanohog!) and (2) buying all those mounts doesn't take up any inventory . . . neither do vanity pets or titles. Tabards still do, but I am less excited about those anyway. With all the downside removed (as well as the dailies being much easier with a lvl 80 DK) I'm blowing through the quests and having a much better time doing it.
As far as the dungeons go, sure it's fun to run them, but it's made more fun to try and figure out how to complete them with an overgeared, yet understaffed party. My brother and I (DK Tank and Enhancement Shaman) and various 1-3 slots of dps managed to get through the heroics with only his occasional chain heals, but it wasn't easy all the time. We tried to get though all the dungeons fighting as few mobs as possible which is easier in Steam Vaults than it is in Shattered Halls, I can tell you that much.
Anyway, it seems that I am easily swayed by achievements and vanity pets/mounts that don't really matter in the game. But then again, doesn't anything in the game really matter? I'm having fun and I like it, so I guess that's what it's really all about.