We have iOS 5 beta 1, we have Notifications Center and now we have a first method to change the background of the new notification center. As Apple will probably not give us the possibility to change this background without jailbreak, here is a very simple method to change it. Of course, you need a jailbroken terminal on iOS 5 and ifunbox or iPhone Explorer to access the system files of your terminal. After you have opened your favorite utility and connected the terminal to the PC, navigate to Systems / Library / CoreServices / SpringBoard.app. In this location you will have a file called BulletinListLinen@2x.png, this is the image that appears in the background in the Notifications Center. Save it on your computer before following the explanations below.
The respective image has a resolution of 960×640 (height&width) for iPhone 4 and if you want to modify it, you must look for another image in png format that has exactly the same dimensions. After you have found an image with the same dimensions that you like, rename it to BulletinListLinen@2x.png and copy it over the existing one in Systems / Library / CoreServices / SpringBoard.app. After copying the new image, respring your terminal or if you can't respring, close it and reopen it. After reopening, you will find that the new background image of the Notifications Center is the one you chose. I don't know the dimensions for the iPad, but I imagine we're talking about a larger image. For iPhone 3GS, the image has a resolution of 320×480.
