I agree that you should do your research before deciding on a new city. I also agree that Phoenix sucks, at least in the few times I have passed through there, it kind of struck me as one giant, boring strip mall. I actually think Tucson is pretty neat, though. It is not as conservative as Phoenix, and I think it has a lot to offer in terms of culture. I like how Tucson embraces the fact that it's a desert. Instead of trying to grow fancy green lawns (which waste a ton of water), they plant a wide variety of cacti and desert plants, which look really cool IMO. 4th Avenue and downtown have a lot of neat bars and restaurants. Also, the Mexican food here is really good (surprise, surprise).
That said, it is really hot here. Especially in the summer/early fall you will not want to spend more than 15 minutes outdoors at a time when the sun is out. After sunset, I found it to be at least tolerable to be outside, probably because of how dry it is. We do have Mt. Lemmon nearby (>9000 ft at summit) which you can drive up and escape the heat. On the flipside, winter weather is really nice. Also, there are a lot of good hikes in the mountains surrounding Tucson.