This is what I did too. I considered the quality of coursework, funding package, overall school culture, advisor's work, advisor's attitude and willingness to work closely with me, location (I'm moving with a partner, so he had a say), research opportunities, and publication opportunity.
Honestly, I also went with my gut reaction. I have a very good feeling about my working relationship with one of the advisors. Our interests are a good match, she is talented and accomplished, and she is rooting for me! She even increased my stipend to include fees and health insurance (tuition covered by scholarship). An unhelpful advisor is a big fear of mine, having watched friends work on their PhDs in various fields. Plus I already know what research projects I will be working on and I know they interest me. Another fear of mine is committing to a program and having to search for projects I like and maybe not getting them. No, thank you. No surprises, please.
Any other criteria people are using?