Okay, I've only been to Dozen Bake Shop once, so maybe I'm not really qualified to write a review, but Pittsburgh needs some Yelp help.
I purchased, and enjoyed, a humongous cinnamon roll with--pardon my word choice--HELLA frosting. It was incredible. What's more impressive is that I left the cinnamon roll in a car overnight and for the better part of the next day before I consumed it, yet the roll was still tasty as could be. I also tried a bite of a Mostess/Mostest? cupcake--aka a Fauxstess--and it, too, was incredible.
As for the non-food aspects of Dozen Bake Shop, I like the tasteful interior decorating--cute, but not over the top--and the guy (the owner, maybe?) who works there is very nice. Prices aren't too bad for the quality, either. I'll definitely return to indulge my sweet tooth.
Update: Now that I've tried several items at Dozen, I can say that I am thoroughly addicted to the danish with blackberry or blueberries, which is the best I've ever tasted, and the red velvet cupcake.