Thanks to this thread as well as a few blog posts and other resources, I'm happily computing on my 120gb ocz vertex 2 + Caviar Black 2TB.
A few tips for people about to get at it:
-No matter how good an idea "anti-static gloves" may sound like, do not let the salesman talk you into them over a wristband. Working with those on was so incredibly clumsy. Goodness.
-Having used my torx set to add an SSD in my previous 24", I figured I had all the tools I needed. Wrong. You need "precision" torx tools, as the displays torx screws are recessed about a half centimeter too deep for my "torx multi-tip srewdriver" to reach. My screwdriver was a bit too fat to wiggle in, so I ended up using just the tip and some pliers to get them.
-Don't bother with trying to "just lift" the logic board. I got fed up after an hour of trying to get the SATA on and just unplugged everything and took the board almost totally out. Much easier, and I am hardly "experienced" at this stuff.
-Remember to TAKE OUT YOUR RAM! It slipped my mind for a bit and after I took it out, the logic board came right out.
-No suction cups required. Just Use your fingernails.
-When looking at blog posts or tutorials detailing the procedure, pay CLOSE attention to the orientation of the iMac. I was quite confused at points, because they had the iMac upside down in one photo, or something of the sort.
-I ended up unplugging the HDD SATA and plugging it into the "SDD" designated slot, and vice versa. I thought with the angled connector it fit better this way. It is mis-labled in the profiler, but everything works as it should.
-Don't even bother with "mounting" the SSD. There was hardly enough room to even jam the y-splitter in there, I don't know how people fit a cage of any sort inside.
-Don't let the little stuff slip your mind. Case in point: I had the iMAc back almost totally re-assembled and booted her up. When it asked me where to install the OS, no drives showed up. "OH S$%$^" I thought, and tore the machine apart again. Then I realized that I did not format them with disc utility, only after I had taken the LCD off again!
As for the fans/temps, I just installed SMC first thing, and set the HDD fan at about 5k. Running at 99 degrees just fine.