There is no such thing as bad publicity and i doubt that big companies even care for non-professional endusers (read : gamers).
What they are concerned with is when other major companies who use their cards by the thousands get pissed.
Imagine John Carmack writing a column that nVidia and Ati both suck and decides only to optimize his code for Doom III for the Matrox Parhelia. That would get their attention , but would they care for it much ? They will find another minion for their work.
I sincerely doubt major corporate companies will implement a new videocard based on Dawn , 3dMark 2003 , Doom III or Half Life 2 screenshots.
I've been trying to study nVidia's Cg language for a while now and i must say it is pretty impressive (for me). Will i ever use it to render my own cool Doom IV implementation ? Nope.