Interestingly enough, Samsung are just launching some fun displays...
Samsung SyncMaster XL24 LED BLU 24" Pro
Samsung SyncMaster XL30 LED BLU 30" Pro
Both are LED backlit, and both are horrifyingly expensive right now, but these use precisely the kind of panel that Apple "should" be looking to incorporate into their revised displays.
I have a suspicion that once the price of the Samsung panels (or the equivalent from one of the handful of manufacturers out there who make the the components rather than just box them up with some electronics) comes down a bit so Apple can charge around their current price point and still make around 35% margin then we will see revised displays. My guess is that it will be towards the end of the year (which coincidently is the deadline apple announced last year for eliminating the existing nasty environmentally unfriendly displays they use in everything except the MBA, MBP15s and some MBP17s).
ACDs many even almost be good value for money at that point. Much like they were when first introduced.