This is an interesting conversation! Vishal talks a lot about Pentagram. If you haven't seen the Global Metal section on India yet, I'd recommend that, too! I'm not a huge metal fan but I can appreciate it.
I am a MASSIVE rock music fan. And obsessed with stories of bands and rock history. I still think Rock On is one of the best movies about being in a band that I've seen. There's something really specific about the bonds of being in a band that's hard to capture in fiction, somehow. Like the inverse of Inside Llewyn Davis. (Which was also excellent.)
The daily gossip hasn't revealed that much, although I have a feeling we're going to be bogged down with Happy New Year "tidbits" until it releases.