Is there really any difference between the different brands of Memory? What should I look for? Should I just base my decision on Cas Latency, price and color?
Usually just quality. But I don't really think there's a difference. As far as what you should be looking for, I can tell you what you shouldn't be looking for: anything with a fancy heat spreader. RAM doesn't generate an appreciable amount of heat, even if you overclock it. CAS latency, while I'm sure improves performance in some areas, should be a back burner stat to look at, mostly because the number by itself means nothing.
So that just leaves price.
Why do you think AMD cards are better at video editing then Nvidia?
What are you basing that on?
Someone else here would say a video card doesn't matter much in the end, because most of the heavy lifting is still done on the CPU.
Do some research on the programs you're running. If there's a lot of support for CUDA, then NVIDIA wins out. If there's support for OpenCL, then AMD's latest offerings win out (NVIDIA didn't put much weight GPGPU functions on the 600 series). If there's no support, a video card doesn't really help.