Will Natty run without a PC BIOS (i.e. with UEFI)

There are plans to remove bios from new computers. Is Natty prepared for this? Will it work when I buy a newer hardware or should I buy older pc?

you can run any gnu/linux distro without bios(uefi that is) since 2001-2002.

grub-efi

The current linux kernel available on Maverick was built with EFI support:

grep _EFI /boot/config-2.6.35-24-generic-pae 
CONFIG_EFI=y
CONFIG_FB_EFI=y
CONFIG_EFI_VARS=y
CONFIG_EFI_PARTITION=y

If you are buying an PEW if possible please test drive it with a live cd, unless you do an exhaustive support check for each component there are some chances that something will not work as good as you would expect.

Since Kernel 2.6.25 EFI is supported in all modern Linux distributions - this also includes 11.04 Natty. You could also have Coreboot with GRUB2 payload to boot without a BIOS.