Noisy fans??? I never hear my fans. Yes, the case produces heat, but that's also because the case serves as a heat sink to pull heat away and radiate it off. Even when pushing my Mac to the fullest with running Pro apps, Creative Suite software, ProTools, etc. my fans rarely kick up speed to the point where I can hear them (and even then, the fans are quieter than the one in my cable box).
Even when the case (on the top) is very hot, the internal temps are perfectly fine, no complaints here. (and yes, the display is absolutely phenomenal)
Just a couple things. Pro tools and Adobe CS do not push the iMac to it's limit. Or at least not very often. Unless you have 50+ instances of Trilogy loaded. You'll usually run out of RAM before you over tax you proc. 4 hour multi core video 3D renders push it and the fans with it. What are your temps at idle? They should be no higher than 40-50ºC at idle. According to documentation the i7-2600 max tcase is 72.6ºC. Prolonged temperature close to or beyond that increases the chance of damage or thermal shutdown. Mac Pro's idle well below this thanks to the large case and all the space in the world for heat sinks. Never higher than 35-40ºC in summer at idle.