Regardless of what it's called, some of the chosen background colors covered by the gradient mask are too dark, and as viewed on my iPhone 4, look like a solid black background. Especially the Bears, Texans, and Packers; from most apparent to least. This problem is not as apparent on my H-IPS calibrated display, save for maybe the Bears. The target device and audience should always be considered for any successful design. I just thought I might mention it, as the gradient consistency between wallpapers seems lacking for the above mentioned examples.
Thanks for making these. Though I must say, as a Chiefs fan, I doubt I'll be rocking these any time soon. They consistently depress me. Maybe in another year or two.