I'm always ready to stir crap up and have a fight, especially on this topic, which I was arguing with Rob Repp from T$R in 1994 on USENET over. I'm also a lawyer, though not an IP lawyer. I have to say, to pick this fight in this way is stupid. If WOTC didn't go after this guy, it would set a bad precedent. They almost HAVE to. It seems to me to clearly violate the OGL.
Hopefully a C&D letter works. If it has to go to court, then the ripple effects of some idiot judge's opinion might be bad. You never know what a judge is going to say or do. Thankfully, I think WOTC's lawyers know this as well, so they will try to bury this guy fast and get it over with out of court, likely by attacking his means of distribution and payment, if the C&D letter doesn't work.
I can't believe I'm rooting for WOTC to quickly crush someone legally for a position of theirs for which I despise them.
But the potential collateral damage could be too great for the rest of the OSR publishers, whether through court decision, or due to some weird internal corporate dynamic, where we wake the sleeping dragon and it lashes out indiscriminately at everyone.