Another use for face detection would be a smarter zoom feature that would centered in on faces in an image when zooming in. I'm on a 30" screen and like to 1:1 for sharpness judgements, but hitting the mouse to reposition the zoom cuts down my insane processing speed. Face sharpness is king.
Thanks Rob, I think I have that on. I wasn't clear on my request. When I'm strolling through my images, I'm using keyboard shortcuts to flag and rate can color-code images. I'd love to be able to see the full composition, then hit Z to zoom in. Z center zooms. I'd like Lightroom to either deduce the faces or use face data from cameras to zoom in on the face or group of faces. That way I don't have to click the mouse nor reposition the image to judge the most critical part of the image: face sharpness.