Actually it isn't as either clear cut or "simple" and easy as just simply being the use of the card. The idea is "does the technology use by Nintendo lead to monopoly usage" and that answer is no and is really closer to a frivolous one really.
Tons of the posts here are getting idiotic on homebrewed systems and actions to be honest. I mean really guys, whether it was Napoleon, Reggie, Eklipz, Nuclear even yours Twitching. The basis of the lawsuit is not so much the card itself, the basis is the intended purpose of the card; a card designed to do nothing more than circumvent and namely allow for the use of illegal actions on th device.
This itself mirrors torrent cases where a company gets sued namely for the development and distribution of software and means that predominately support activities that are in the realm of pirating activities and Mr. Fernandez is saying "omgz I don't know that they are pirating illegally I just supply the means". That in itself is a weak case overall and Nintendo has the upper-hand more than most of the posters realize.
Thirdly, seriously people, can we just all stop being douches of the "omfg it better be free or pirated because if not, well F* company (insert name)" because this attitude and complex is getting more and more childish. So a company is not taking matters sitting down when it comes to asking to be paid for itself. Yes I see how its a crime to actually request to be paid. Obviously tons of you who posted in support of Fernandez also like to work for free and not get paid for what you do as well.
Worse yet, a company goes into business to make a profit, whether its Xbox, Apple or Sony or Nintendo even. Frankly when it comes to posters on these forums you have few issues with Apple making money (despite their attitude being more rigorous on product control on the company end) and yet feel more than happy to dish on other companies. Yea this double standard is equally as idiotic.