Stop talking rubbish, there is NO improved screen, Just that the screen is now closer due to thinner glass. Yes text my look better, Last time I checked Apple wasn't talking about a revolutionary screen but saying how thin it is. Please get your facts right.
Old 21.5 base had 7200rpm HD this new one has 5400rpm hd, = lesser component and price increase, No optical drive and price increase, with such a nice computer one would likely stick to apple, thats price increase of £99 plus Apple external for £65 all for lesser components but more money.
You can stay blind or be ignorant, thats your prerogative.
I said "screen assembly", not just screen. Apple has noted at least 3 improvements:
1. Elimination of the air gap. This does NOT just make the screen "closer", it eliminates a source of additional reflections and makes the image slightly crisper.
2. A new anti-reflective surface layer.
3. Individual display calibration.
Apple says the new screen assembly is 75% less reflective than the old one. That is probably a very significant chance, but I'll reserve judgement until I see it in person.
As you noted, some of the new disk drives spin slower than the old ones. If nothing else changes, that will definitely result less disk bandwidth and longer latency. How much worse the drives perform remains to be seen. There are lots of other variables that affect disk performance: cache size, number of platters and number of heads, total drive capacity, etc. You chose to mention only the rotation speed. If that's your most important feature, fine.
The "last time you checked" Apple's descriptions of the new iMacs may have been somewhat incomplete. Here's a web page:
http://www.apple.com/imac/
They mention the new thin screen, and then they mention the 75% improvement in reflectivity. So we're both right about what Apple is talking about. I'm NOT calling your post "rubbish" just because you chose to ignore some of Apple's description.
Other "components" have clearly gotten better... the CPUs are better than before, the graphics are better, the memory speed and capacity are both better, the USB is better. The (optional) SSD may better, but we don't know for sure yet. The (optional) fusion drive is better. Is it ok if I call those things "components"?
Yes, they no longer include the optical drive. That undoubtedly lets them lower the price (or in this case increase the price a bit less). It also removes a significant source of heat. I guess Apple thinks most customers will be ok with these tradeoffs. That may not be true in your case, but they aren't trying to please everyone.
If pointing out some improvements that you didn't mention makes me "blind" or "ignorant" in your opinion, that's ok with me. No rule says we must have identical opinions.
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Since "Available in November" for the 21.5" really means you won't be able to put your hands on one till December I'm guessing the Mac Pros "Available in 2013" means they have been discontinued.
According to Apple's announcement today, I expect quite a few people will put their hands on the 21.5" iMac this Friday, November 30, 2012. "Coming in November" has never meant that everyone who wants one will get it in November, but some people will.
