The i7 975 is a nice CPU and one that will fit nicely at the top of the Intel i7 line-up. The performance in rendering was very impressive and cannot be overlooked, but in the end if you are doing media encoding or are a gamer there is not much to be had with this CPU.
Overclocking was a little bit of a disappointment with all of the hype about people getting 5GHz on air cooling. However, we will be looking further into this issue and we expect that many will hit a similar wall as we did.
If you want the best of the best the i7 975 is the best single socket CPU solution you can get and it will certainly improve any content creation you are considering. But for the majority of us the i7 975 is still a little on the expensive side and the gains might not be worth the extra cost right now.