If anyone else is annoyed by the 12 app limitation of Apple’s iOS 4 Folders, there’s a tweak available to jailbroken iPhones called Infinifolders available in Cydia for $1.99.  With Infinifolders, you are able to put as many apps as you want into a folder, choose the color of the scroll bar and paginate the folder.  I find this teak very useful and highly recommend it.