dude, this looks great and i will try it really soon.
btw. in iOS 7 (for both iPhone and iPad) there's this new parallax effect (hard to explain what it is so you might just want to look it up on apple.com) and if you'd like to support this effect with your wallpapers, then you might want to consider adding 200px to all sides, because otherwise all regular sized wallpapers would get zoomed in, which make them look kinda blurry and not very good. well, this might not be that troublesome with walls that are blurry or just color gradients to begin with, but i thought i just tell you.
well, here's a link for you from where you can get more information on this.