There's a 32-bit EFI bootloader available on my site at http://helium.hexxeh.net/joggler/
This doesn't yet work, but with a bit of work, could let you boot Vista/7.
The above is only useful to boot Windows PE off optical media (and in particular, etfsboot forms part of an El Torito system 0xef boot image). What we really need is the 32-bit EFI bootloader for hard disk boot found in Vista build 5308.
The best hope for Windows 7 at present is work on a Coreboot and SeaBIOS port which is currently in progress. See here: http://www.jogglerwiki.com/wiki/Joggler_Coreboot_Diary