It's a hot topic right now and there's lots of discussion out there and not all of it's accurate.
Here's a link to a series of articles about quilts and copyright from Quilter's Newsletter Magazine that's fairly understandable.
Here's a question for you - if you make a quilt from a published pattern are you allowed to post a photo of YOUR quilt on your blog or on a photo site such as Picaso or Webshots? And how many of us have seen quilts from published patterns in quilt shows? Read the above articles and tell me what you think.