From what we know so far -
big model line-up story here - it appears the model number ends with '10' it's Full HD/1080p, and if it's '1' then it's HD Ready/720p.
Though there could be exceptions - manufacturers' means of naming models never cease to amaze/infuriate me.
People had just got to understand Panasonic's naming conventions (TH meant plasma; TX meant LCD; Z meant Full HD, X meant HD Ready) and now they seem to have changed it.