HD didn't make SD look worse, it just showed it the way it is. HD on 4K (or quad-HD) displays looks just like HD, you can't see the difference. Good upscaling algorithms can bring some benefits, just as we see up-scaled DVD out of Blu-Ray players looking pretty good, in many cases giving Blu-Ray titles a run for their money. The big issue we have here is that many HD sources and Blu-Ray releases are just not of very good quality. There are many factors, some of the biggest being over-compression and poor compression algorithms, clipped and compressed color spaces, that sort of thing. Apple is that wildcard rumor. And I actually do expect them to go 4K with their TVs when they launch. I don't think Apple will be launching their TV product in 2012. I bet it happens in 2013. What I do expect to see first is updated Macbook Pro and Macbook Air systems with "retina" or double-density displays. New iPad with the same. Next they will move on an updated iMac with double density screen and I also expect the new iMac to have many of the rumored TV features to be incorporated. Also expecting a 25" (yes, 25 inch) cinema display with actual 4K, 4096 pixels wide, resolution. ...I have my reasons/sources.
Blu-Ray consortium is hammering out the Blu-4K spec right now. RED *NEEDS* to launch RED-RAY (or RED4K, or whatever it will ultimately be called) this coming year.
Oh, and Toshiba is first to market with consumer 4K displays. They're officially launching them friday (less than 48 hours away) in Japan. Should hit state-side in about 5 months. The 55" no-glasses 3D model is their flagship display, but they also have a 55" 4K without the no-glasses 3D (I don't know if it does 3D at all) for 650,000 yen, or about $8200 USD. 4K is here.
Sony will be showing 4K out of a PlayStation3 at CES next month. Surprisingly, I'm not under NDA about that... I don't have details though. They should also be showing preliminary 4K Blu-Ray content.




33-megapixel CMOS Image Sensors for UHDTV2; [7680 x 4320/59.94 p, (RGB) 4:4:4]. (SMPTE Members can find the whole text in pdf via the link).