Eurogamer has a statement from CD Projekt to the report that they are sending letters to those accused of pirating The Witcher 2: Assassins of Kings. While restating their strong feelings about not using DRM, they clarify that this does not mean they are okay with their game being stolen:

However, that shouldn't be confused with us giving a green light to piracy. We will never approve of it, since it doesn't only affect us but has a negative impact on the whole game industry.

We've seen some of the concern online about our efforts to thwart piracy, and we can assure you that we only take legal actions against users who we are 100 per cent sure have downloaded our game illegally.