I think it's a wonderful Russian name. It's not difficult for people who aren't familiar with the language to pronounce. I like it and it's growing on me more each day.
My mom's friend adopted a little girl from Kazakhstan named Zhanna. She's about eleven years old now, and she likes her name. The only thing is she thinks it is a little hard for people to pronounce or spell when meeting her, but after the first time, they don't ever forget. It sounds a little different and exotic, but not too weird-sounding. I think it's a good name.