iOS 18 May Enable Users to Customize Layout of Home Screen App Icons: Gurman
iOS 18 may enable users to customize their Home Screen apps more with added options for layouts.
Apple has released iOS 6.1.3 beta 2 to developers and according to the release notes it fixes the passcode lock screen bug along with some other fixes for Maps for Japan (via 9to5Mac):
iOS 6.1.3 beta 2 includes a security fix for a Lock screen bug and the following improvements to Maps for Japan
Prior to this, developers had access to iOS 6.1.1 beta but this has been renamed due to the recent release of iOS 6.1.2 to fix the Exchange Calendar bug.