Looks like I'll be building my own systems for a long time to come. I don't mind buying a PC with a copy of Windows pre-installed, but I draw the line at Windows-locked motherboards.
UEFI is a bit like IPv6 in that there's a lot of talk about it, and very little visible implementation. None of my newer PCs have EFI or UEFI.
Many Linux distribution maintainers have said that they are working on bootloaders that will work with the Windows (in)security key. So it may end up being a non-issue. Companies like Dell that make large profits on data center class machines (that often run Linux) aren't likely to just walk away from half or more of their income base just to appease Microsoft. It will be interesting to see how this unfolds though.