Dark shadowy areas on 32" Vizio LCD HDTV

Recently I noticed some dark shadowy areas appearing on the lower half of my 32" Vizio LCD HDTV. It is mostly noticeable on lighter colored screens. Check out the images below and let me know if you have ever seen anything like this before. If so, any ideas on what causes it and how it can be fixed? Luckily I have an aftermarket warranty...