Simply put, LG doesn't think that 1,280 x 720 on PenTile counts as HD due to the lower number of sub-pixels; and while it's at it, the company also criticized AMOLED's over-expressed colors and higher power consumption in "normal user environment" -- for the latter, LG showed that its AH-IPS has a more consistent power consumption across varying levels of overall whiteness. You can see the relevant slides after the break.
Of course, we've already expressed (twice) how much we like the HD Super AMOLED display on the Galaxy Nexus. The clearness issue now is much less noticeable when compared to the original Super AMOLED; but as for color accuracy, many of us are indeed deceived by the vibrancy that we naturally enjoy -- except when you need to inspect photos, of course. Regardless, we're pretty sure that it's only a matter of time before Samsung strikes back with a, ahem, "true HD" Super AMOLED (Plus) panel -- hopefully in time for the upcoming Galaxy S III.