For video editing, depending on the software, more cores usually its better, but again depends on the software, so if you like AMD i would try to go with AMD FD8320FRHKBOX FX-8320 FX-Series 8-Core Black Edition
, memory is also dependant on the software will use, amd benefits a little more in performance on faster ram than intel so i would consider a little above 1600, maybe 1866/2133, whatever doesn't increase drastically the budget, go with standard height, avoid high heatsink on the memory or it might affect the choices you have for cpu cooler, on the amout will depend on the software, but 8gb as minium and recommened 16gb, above that cross check that the software will be able to or benefit from more than 16gb of memory.
An 8-core CPU seems a bit much though. As for RAM, I did find some 2000MHz RAM in the same Corsair series, but I'm not sure about this as motherboards don't seem to list it. I was specifically looking for the 'standard' size to avoid compatibility problems (also for price reasons).
if you like noctua, then i would consider the NH-U14S
, also reviewed by SPCR Noctua NH-U14S Slim 140mm Tower Cooler
, doesn't get as much recommended mostly for the price, but its a superb single fan cooler.
These two Noctua heatsinks are actually ones that I chose based on the reviews at SPRC, along with the PSU. I also discovered Noiseblocker fans here.
On the PSU, similarly priced, i would also consider the Corsair RM Series 650 Watt ATX/EPS 80PLUS Gold-Certified Power Supply - CP-9020054-NA RM650
, for $110 you get a gold rated PSU, fully modular and very quiet, 650 should be more than enough even going with a high end GPU later on.
This looks like a good PSU but one thing I've avoided is a PSU with the fan only starting up under load.
Case, i would look for something like Fractal Design deifne R4, Corsair 550/330, Antec Solo II, etc, even more silence oriented, but since you said its more for looks, then go with whatever you like.
There are a lot of good cases available, though they tend to get too 'fancy' with noise-reduction and airflow. I figured that if the cooling is adequate inside the case, then it shouldn't matter as much on the type of case I use. I've avoided cases with padding on the sides (to help with noise) because this seems detrimental to cooling, and the same with cases with an extra front panel. On the other hand, cases with extra top fans for cooling would seem to make more noise due to the position of the vents. Although, I would consider some of the BitFenix cases with top fans if they didn't also have those bottom fans.
I would also consider intel as option, will be slightly more expensive but, depending on the software, might be more capable, the 4770K/4670K come with intel hd4600 that should be sufficient for anything that its not gaming, even mulitple screens, video playsback, even encoding with quicksync, but if you are keen to AMD, go for it, its not a bad choice either.
It's more brand preference really, because that's what I'm using at the moment, but I'll look into Intel as well.
What program(s) do you use for editing and at what resolution/quality level?
I use VideoPad, which I use for 'hobby' video editing, and also MediaCoder. The output resolution is 1024x576, as this seems to be the one that has worked the best. The input resolution is 1280x720 and 848x480.
I would totally scratch the APU. If you want to use this as your intro to a professional system, then you need to build it right the first time.
It's not professional video editing though, which is why I haven't been looking into the system requirements of the professional suites. I did check out the Intel Xeon series in your signature, however, which is listed on the distributor's website as a 'server series'. I probably wouldn't have researched anything with a price point such as that though, as it's pretty expensive.
On the other hand, I just checked the system requirements for Adobe CS6 and they don't seem that high, though they haven't listed 'recommended' system requirements.