You could go to the websites of the magazines to get an idea of their covers (usually the featured quilts), colors and patterns. On some of them, if you click on a magazine cover you will see photos of all the quilts inside. Here are the websites:
http://www.fonsandporter.com/issues/index.html (Love of Quilting)
http://www.mccallsquilting.com/mccal...ues/index.html (McCall's Quilting)
http://www.quiltersworld.com/shopping.php?mode=archive (Quilter's World)
http://www.quiltersnewsletter.com/issues/index.html (Quilter's Newsletter)
http://www.quiltmaker.com/issues/index.html (Quiltmaker)
Quilter's World is probably the most traditional, with Quiltmaker also tending towards traditional patterns. Quiltmaker provides detailed, step-by-step patterns for each quilt; for me it is a little too staid and rigid. Quilter's World is more chatty and often provides some interesting stories and history. I think Love of Quilting tends to be pretty traditional too, but I don't have a lot of experience with that one. McCall's provides a good mix. Quilter's Newsletter nowadays tends to provide more quilting news -- quilt shows, quilt artists, etc. -- and tends to feature more complex quilts.