Loved, loved, LOVED Orvieto. We stopped there enroute from Rome to Florence.
First of all, it is darling.
It is very easy to get into and out of.
They have an amazing Duomo, plus many unique features that my family continues to talk about: the well, the underground, the cloth that was bled on by the bread (believe the story or not, it was a very interesting story), the fununcular (that doesn't look right by I can't remember what it was called if not that) that gets you up the hill.
I didn't find it nearly as touristy as Venice or even Florence. It was very quiet a month ago.
Highly recommended by our family!!
For pictures, check out Ron in Rome's blog because he really sold me on it before I left. I rearranged our whole schedule to go, and we are all really glad we did!!
Have a wonderful trip!