News in from several sources (including vendors) is that Pro Tools HDX is selling, in some cases it’s selling out. There is some stock still in stores, but Avid have run out and are now working on getting more stocks into the dealers, no one at Avid would confirm numbers sold.
From what we can ascertain, there has been a large take-up in hardware upgrades which has fuelled this early adoption, it’s also important to remember that Pro Tools 10 gave many HD owners the final warning on compatibilty with the future 64 bit version.