I feel extremely fortunate to have worked with these displays for the best part of my academic life. Just because Apple can refresh their product line up annually does, sadly, no longer mean that the product is any better. In the Cinema Display's case, this is far superior for any kind of graphics work than their latest glass + aluminum effort.
What I feel is wrong with Apple's current production ethos is that, in many cases, design comes first. So ok, it's a well known fact that Glass provides better colour saturation, but what good is it using this glass when the display panel isn't even sitting on top of it close enough? It has no depth at all, and so the sky rocketing production costs (due to helping nature) earn them more profit through silly prices. Well I'm not going down this alley.
This previous generation 20 inch Cinema Display is absolutely flawless. The display actually sits directly behind the anti-glare screen, meaning that you get stunning clarity and almost 'depth', where the images look 3D. 2 USB ports are provided, which is brilliant if you have any USB powered peripherals lying around and your Mac is sitting below (very handy for portable HDD's that don't get taken away regularly). Their are also 2 Firewire 400 ports - Yes, these have been superseded by 800, but speed isn't really my thing. Plus, my white MacBook has FW 400 anyway.
On the side of this display are power and brightness buttons - since the display has a USB cable which can be attached to your Mac, the Power button can also control sleep mode etc which is very nice.
Bear in mind that this display outputs through DVI, so if you're planning on using this with a current gen MacBook, you'll need the DVI to Mini DisplayPort adapter. Mac Pro's are fine because they have both DVI and Mini DP, while 2006-2008 MacBooks will have Mini DVI connections, meaning you'll need a DVI to Mini DVI adapter.
I think I've said enough... Theirs just no need to pay for the new Cinema Display.