That's clever marketing. They actively lock out Windows XP from their Intel macs, then they act all like "Okay, so now we'll do Microsoft's job because we're nice guys and they'd never get around to do it right"
"Actively lock out"? You mean, by actually using modern technology instead of software remnants from the darkest parts of the eighties?
The BIOS is a horrible, horrible kludge, and the faster it's gone, the better. MS deserves every bit of abuse they get for not supporting the alternatives.