The case will have a spot for a 120x25mm fan on the side, so you could add one there. If you don't plan on overclocking, you don't *need* an aftermarket heatsink/fan for your CPU - that case has plenty of good airflow. Your CPU will be sitting right next to that HUGE top exhaust fan and 2 rear 120mm fans.

Looks like a kickass machine. If money isn't much of an issue, why not add a $200 32GB SSD drive to host the /data directory of WoW? That's about final bottleneck you're going to have. The Velociraptors are incredibly fast, but they can't compare with the access times of flash memory (.22ms SSD vs 5.9ms Velociraptor) I'm waiting to hear back the results from someone who's tried this, although I may end up being the first..

The main bottleneck of WoW is small random reads from the hard drive. Any time a player walks into your "area", the hard drive has to be read for all objects & textures on that player. This is a big reason why cities are a problem - there are so many small files to load into memory. Of course, there are a lot of polygons and processing too, which is why the CPU, RAM, and videocard combo are all important. However, compare the chart for "random read performance of small files" between an SSD and Velociraptor.. it's not even close:
http://www.xlr8yourmac.com/IDE/SSD_v...or_Raptor.html
SSD: 18021 vs Velociraptor: 676. This is for the bandwidth in accessing and transferring 10KB files, in KB/s. The most important aspect of WoW bottlenecks, by far. And for this test, the Velociraptor had to be formatted to a 32GB partition for maximum performance (smaller area to search = faster times), which virtually no one would do to a 300GB drive.