man...let me tell you something....those displays rock!!! Plain and simple...they're vibrant..alive..you dont mind staring at it for a lengthy amount of time..and let me tell you..I spend ALOT of time infront of monitors..I wish I could afford one of those!!
Just my $.02 worth
Opus

Pro's & cons after switching to Apples from bananas (ie 'normal' monitors):

pro:
- Substantially less headaches after working long hours.
- Don't need to put my glasses on-and-off-and-on-and-off-and, well, you get the picture
- Working marginally faster.

con:
- None

i would imagine the con is money.

then again, if you're not paying for it, let your buddy live out his dream, and share the magic!

p.s. Opus, when you're influencing someone to buy a cinema display, it's less of a $.02 and more like your $2,499 usd worth :p .

Pros:
No interference with audio equipment
Don't need to have AV monitors speakers, so better range of choice.
No flicker -- this is particularly important if you work with other monitors or fluorescent tubes. It will reduce headaches a lot
Lots of screen real estate, more useful format than the old 21 inch monitors.
Very bright and crisp -- easy to calibrate if you also need to proof design work.
You can use the VGA output to hook up another monitor in addition.

Cons:
Money.