Mueller has been quietly working behind the scenes, giving the usual DoJ courtesy of not influencing an election with announcements about an ongoing investigation (looking at you, James Comey). Of course, he was probably also shielding himself from what would have been a nasty presidential tweetstorm and probably getting fired. He might still get fired, and Sessions leaving puts us one step closer. I think Mueller will probably want to act pretty fast if he's been sitting on something he feels needs to get out, and this news only hastens that. There's a lot of rumors out there concerning Roger Stone and Trump Jr., but I have no real way to gauge how substantiated they are. But this was solid reporting indicating some action behind the curtain (I know you saw it, posting for posterity): As for Rosenstein, good question. Supposedly Trump and Rosenstein have a good rapport, despite the wiretapping story a couple of months ago:
When I have time for reading non-journal articles (and news articles), I might check it out.