The back of the LCD display has only a few cables, none too exciting:

DisplayPort

LED backlight

LED backlight sync

Ground loop.

The LG display reads model number LM270WQ1. Is it possible that we may have seen this model number before?

Yes, it appears to be the same display found in the iMac Intel 27" from October of 2009, as well as the same basic LG display found in Dell's competing 27" monitor, though the Apple version uses LED backlights as opposed to Dell's traditional CCFL.

Dell's version is also matte, something that lots of Mac users have been harping for once the old 30" Cinema Display was phased out.