The thing is, there is no $500 alternative on the market. At least not yet. Look at the retina display capabilities on Apple laptop computers. That resolution far exceeds that of regular HD TV sets. I would expect a new offering from Apple to have capabilities mirroring their high-end monitors. You can hook up a computer to an HD TV and use it as a monitor, but you will be limited to inferior HD or 700i resolution. Samsung sells some excellent HD TVs that work well as monitors for computers. But if you want retina display quality with four times the resolution as HD or better, then Apple may be the ticket for now. I may be wrong; if so, please point out existing higher than HD resolution TVs on the market for $500.
First, Apple will no more waste time on 2560 x 1440 TVs than they would waste time on an IPhone with no screen. There's NO broadcast or cable signal source that can push that many pixels. Most "HD" TV is broadcast in 720p in the first place, with only a few specialty channels and sporting events ever actually in 1080p. Even Bluray is capped at 1080p. You would have to be a moron of epic proportions to by a TV for thousands of extra dollars with a resolution twice what your signal actually provides.
Nope... Apple will sell 1080p TVs for twice or three times normal cost, with the up-sale based on control features (think TV + Siri) or content addons (AppleTV builtin, plus subscriber agreements, etc.). And fanbois (and the "trendy" technologically illiterates) will lap it up...