James Bottomley wrote a new blog post this morning about why the Linux Foundation really isn't concerned about UEFI SecureBoot on ARM hardware (smart-phones, tablets, etc) compared to the work they are doing on x86 PCs with UEFI SecureBoot support for Linux.
Last month the Linux Foundation announced their UEFI SecureBoot plans for dealing with Microsoft Windows 8 PCs. Their plans basically equated to legally obtaining a Microsoft key and signing a small pre-bootloader that in turn could chain load a predesignated boot loader that would in turn boot Linux or any other operating system without having to deal with the SecureBoot mess. The signed pre-bootloader will be available from the Linux Foundation web-site for anyone to use along with the source-code, albeit not their private key. The foundation is still working to obtain a SecureBoot key and their SecureBoot focus has just been for x86 hardware.