That is correct in broad terms
However some Video editing software ( Like Avid Liquid) do use graphics cards (GPU) for rendering FX, but generally more Ram and a Decent Processor are more of the norm for better performance
Pinnacle Studio (Ver 10 and above) too takes advantage of a better graphics cards ( especially for background rendering) but this is an optional feature which can be turned off
AFAIK Ulead VS does not specify anything above its minimum Specifications
A decent card is essential for Playback with software like Power DVD ultra for BD or even AVCDH discs though