It's definitely a personal choice, as others have said. I do like, however, to bind the quilt in a fabric that coordinates with both the back and front.

Here is the fabric in question. It is a give away quilt to I don't know who. I don't want to have a ugly one.

This is the best answer ever. LOL cad_queen_rules!!!!

The back is a good place to use up leftover fabric from other projects or fabric you may not like so much for piecing.

I belong to a small quilt guild (less than 20 members usually), and we have small annual quilt show every fall which is open to entries by the public as well as members. Due to space limitations, we usually only have 70 or so quilts. We try to have a different judge each year, often a LQS owner, prolific quilter in the area, quilting teacher, etc. We try to find someone who is not too "tough", as we are more interested in learning from our entries than being "perfect"...in other words, we try to avoid having a strict "quilt police" judge! One year we goofed, tho, and got a real toughie who picked on every little thing. One of our members is a very prolific and talented quilter and does beautiful work. She entered a stack 'n wack that was out-of-this-world in both workmanship and beauty. The judge really complained, tho, that the back didn't "relate" to the front (this was her only complaint on this one) - guess she felt she had to find something wrong. We all had to just laugh at the judge's criticisms of our entries and vow to never have her judge again. We still tease the stack 'n wack entrant, tho, whenever she brings something for show and tell, making her show us the back and voting on whether or not is "worthy"!