I suppose that it depends on what you really are going to use the machine for. The multi-core CPUs out now are good at processing information very fast. It does not appear that we are going to have a breakthrough in processor technology in a little bit. If you use the machine strictly for gaming, I would keep it as simple as possible. Go with the recommended processor but maybe a step or two up in speed or core. This will build some expansion in. Get a board that will allow you some expansion in system memory. More slots or the ability to upgrade sizes in those slots.
I tend to go for the average priced units. Expensive boards are just that, expensive. Cheap boards tend to fail more often. Go for average or slightly above average and you won't disappoint with cost or expansion for that cost.
edit: Something else I just thought of, if money isn't an issue (not saying there are billions available or anything), then you could consider a couple options. One of which is to build a machine that you can plan to move away from gaming when the environments become too demanding. For example, you could retire the machine to a standard desktop or file server after it reaches a certain point. Try to re-use equipment. You could even try to cluster old equipment and create one big machine. (I've never done this so i'm not sure it is even reasonable to suggest, but the idea is sound)
