Coming soon, it sounds like this area may not even be available:
For Mekkatorque, however, his plan goes beyond just reacquiring lost technology. The retaking of Gnomeregan will determine his place in history, either as the high tinker who lost the gnomes' beloved capital, or the one who reestablished it as the center of innovation on Azeroth.
Operation: Gnomeregan is about to get underway.(source)
I guess that I am going to need to revisit this zone, because I really, really want to complete the Classic Dungeonmaster achievement. I am not too worried about Cataclysm closing down this zone, but if I am bored, I should fire up the Wow-Pro Instance guide.