Awesome pizza. It's a neat atmosphere, and one of the few restaurants that I don't feel to bad about taking my toddler into. It took a while to get our order, but they were really busy when we went. There were a line of people waiting outside the door. We were also with a group.
Since my initial review, I've been back to the Mellow Mushroom four times. This place is definitely five stars. The service has been very friendly and efficient, and the food just keeps getting better. Initially I gave it four stars, because it took so long to get our order, but the past four visits have been much better in that area.
My husband and I dined in their bar area late one night, and it was a great experience. The bartenders (Keith and Jenna) were fantastic. I don't think you'd find better bartenders in Phoenix. They were friendly, and made a great drink. They also have a late night menu that is more appealing than your normal late night pub fare.