You will walk somewhere around 3 miles on your average 10-hour clinical day. At my school, we are required to wear white shoes with our uniform scrubs, and most of the students in my class went on a mission to find the cutest ones they could.
From my years of teaching, I have tendinitis in one of my ankles, and have suffered from plantar fasciitis in that same foot. I know that I cannot wear shoes that are not supportive, because I won't be able to walk the next day. I wear Danskos on a regular basis, so I immediately started shopping for Dansko nursing shoes. I found a style that I really liked, and was able to buy them for about $80, with the student discount, from my local nursing supply store. Some of the students in my class were appalled that I had spent that much on my shoes, but I won't have to replace them during our two years in school, and they will last many years afterward, as well.
After a day at clinical, I don't have a sore back or feet like a lot of my fellow students do. I can still walk comfortably, and don't have to go home and immediately put my feet up. So, my recommendation is that when you shop for nursing shoes, you shop for shoes that are supportive and comfortable, not ones that are cute! Here is a photo of the shoes that I have (and love):