What's the relationship between Usenet and Google Groups nowadays? I thought that at some point Google rebadged much of Usenet forums as Google Groups?
It's something like that. As I understand it, Google Groups runs thousands of normal email mailing lists with no connection to Usenet, but it also offers a bidirectional gateway to Usenet - GG'll show Usenet posts that it can download or which it has copies of in its huge archive, and it'll let GG users post to Usenet as well.
You know the drill - If it's worth saying, but not worth its own post (even in Discussion), then it goes here.