OK, another spammer who joined May 27th, and have their posting allowed flag turned on without ever having a first post moderated.
Unless some other list admin is going and flipping this bit in the groups management console (anyone???), this looks like spammers have found some exploit in google groups to get past the moderate-first-post setting.
Other new posters are definitely still getting moderated, I just approved one this morning.
Sorry, I don't have time to look into it. I'll just keep banning them...
*shrug?*
-- Chad