if im not mistaken, it means the tv is ready for high def programming, you'll just need to get the hi def box from time warner (or whatever provider you use)
Yep, it means that you cannot get an OTA (Over The Air) HD signal from the major networks without a HD tuner. If you subscribe to Time Warner/Dish** you are golden.
it has the ability to project the HD signal on the screen, it just does not have a built in HD tuner to decode the signal. You will need an external tuner (like from a cable/sat box, or a stand alone HD signal tuner)
The 'HD package' for cable will cost about $10 a month, and you pay about $5 extra per month for the box, at least that's how much it was with TW before I got DirecTV...