What are you talking about? The 'congratulations' part was just a joke over the 'Minix is in every PC!11!!!1!1!' thing (which, as Brendan points out, isn't really the case - thank you for the clarification, Brendan, the sources I'd seen were very misleading about that part). Tannenbaum had nothing to do with that. AFAIK, Tannenbaum himself hasn't responded to this publicly, and may not even be aware of it.
EDIT:
he has responded now.. Apparently, he was surprised to hear about it. Also, it sounds as if he was trying to make it a commercial system a few years ago after all, contrary to what I said later in this post.
In fact, part of the freak-out over this is because Intel doesn't seem to have told him about their use of his code - though given the fact that it is under the BSD license (since 2000,
according to Wicked-Pedo), they probably didn't really need to.
Besides, the
argument with Torvalds back in 1992 was over the kernel model, not licensing. He certainly never had a beef with Linux getting big - he had a beef with it being a nasty grotty impure monolithic kernel rather than an ivory-tower micro-kernel, and that fight is now over 25 years in the past, something both of them have moved on from long since.
More to the point, he never
wanted Minix to be in regular use -
it is meant as a student model and a research tool, not practical system. It is a kinda-sorta practical system, and a lot more compete than, say,
NACHOS or
Xinu (in the late 1980s, I had first edition copies of both the Minix book and the Xinu book - the latter was the version for the LSI-11, as this was before the PC version was published), but it is still designed mainly to be easily understood. I don't know if he's planning a fourth edition, as the third is now twelve years old, but if he does, it will be in support of his
textbook, which is why it exists in the first place. If he has any reaction beyond, "huh, that's weird, why did they do that?", it will probably be, "But, but, but... it's supposed to be a demonstrator, not an industrial-strength system, it's not up to doing something like that!"