Color choices are important in a quilt. There is a lot to consider. Value, texture, shading, etc. Some quilters find color selection very difficult and agonize over it. Some have great color expertise and proceed with confidence. Others just wing it and hope for the best. (I'm in the last group.)
Today the About.com site has several features about color. These aren't about quilting per se, but may be interesting for quilters. NAYY.
Psychology of Color: