HDMI is a digital video interface just like DVI. It is infact compatible in the sense that you can get an adpater plug that allows a purely digital DVI to HDMI or vice versa conversion. I believe other than the actual pin configuration of the two interfaces the video portions are identical. HDMI also has extra pins for audio. I believe the OP is trying to suggest such a change, because HDMI is becoming a standard for home theater applications and apple could market the 30" display as a HDTV monitor because several cable boxes, newer DVRs, and most new HDTVs are moving to this interface. In my mind, this may be unecessary because cinema displays don't have audio support. And you could simply use a HDMI to DVI adapter to hook up a HDMI cable box, etc to the cinema display. Also, DVI single and dual link connections have the exact same pin configuration, dual link just uses all 24 pins and single link uses just 12 of those pins.