Updating Xcode with SDK 6.0 gives you an error when trying to compile your project.
Missing Retina 4 launch image. A launch image named “Defaultemail@example.com” is required to run at native resolution on Retina 4 devices. Would you like Xcode to add this image for you?
This is solved easily by pressing “Add”. Under Project Summary you can see it has added a new image under Launch Images named “Retina (4-inch)
The image file name is Defaultfirstname.lastname@example.org and can easily be replaced.