I have the same issue of not being able to boot into Windows 8 after installing Ubuntu 12.10.
I followed the instructions on running boot-repair, but it didn't seem to work. My boo-info URL is http://paste.ubuntu.com/1612892.
After I ran boot repair, additional boot options appeared: "Windows UEFI bkpbootmgfw.efi", "Windows Boot UEFI loader", and "EFI/Lenovo/Boot/bootmgfw.efi". I tried them just in case after trying my Windows 8 loader, but now luck.