I knew I'd forget something - cooling!
I have every intention of overclocking this upgrade and even considered going down the water cooling route, but TBH I think I can live with just getting a decent fan for the PSU and leave it at that. The case already has 2 80mm fans at the front and a single 80mm fan at the top and rear of the case. The PSU I was looking at also has a 120mm fan in it so in general the airflow through the case should be pretty good.
One thing is a must and that is that any alternative fan to the stock item must be as quiet as possible and ideally have blue LEDs - I have a windowed case you see and I like blue LEDs! ;-)