My Antec 1200 has 6x120mm fans and a 200mm fan on top. I usually keep it on the lowest speed with the built in speed dials, and turn it up to medium only when I'm playing graphically intensive games. Generally, it's not that loud, although I do keep it under the desk so that might help somewhat.
Liquid cooling? Certainly a very good option for those who can afford it, and aren't scared of the two possible flaws/dangers that come with it - leaks, and bubbles.
Also, for Sandy Bridge vs Bulldozer... Bulldozer is expected to be 50-80% stronger than previous AMD CPUs (more cores, less of an improvement). Lynnfield/Bloomfield was already 30% stronger than equivolent AMDs and Sandy Bridge is 40% stronger than that. Considering that AMD has a history of weak CPUs (and strong GPUs) against Intel's history of strong CPUs (and weak GPUs), it'll be interesting to see how they measure up. That said, Bulldozer doesn't work the same way as Sandy Bridge. Instead of Having each core with HyperThreading, Bulldozer will just have a "module" (which should be the same thing - two threads per module - only with less shared resource conflicts so less loss in performance).
It'll be interesting.