According to this German article (by Dr. Dirk Wetter), out of seven tested console servers (all Linux-based) of various vendors, only two even mentioned that GPL licensed software was used in the product. The majority of the devices did neither mention the GPL, nor make any source code offer.
The vendors have been contacted by the author of the article, and almost all promised to make their devices GPL compliant in the future. It has yet to be seen whether they actually fulfill that promise. I will ask each of them for a copy of the full corresponding source code, since the offer implicitly has to exist [the devices didn't ship with the source code, so 3a GPL is no longer possible].
It's really disappointing to see this happen again and again. Everybody seems to not care at all about the copyright of the code involved.