OldFatGuy: UPDATE: Well it turns out I may not be able to blame Microsoft for this after all. Fallout 4 also had an update of some sort today (I didn't even realize it until I read it on the forum and looked at my downloading history and sure enough F4 updated today). I swear I seem to get coincidences like no one else. Same day... Windows update and F4 update and now F4 is completely unplayable (I just tried again... the tearing is so bad I can't watch it) and I have no idea which is the root of the problem. I'm going to try some new (different) graphics drivers as that's the only thing I know to try now. I have forced VSync on in the Nvidia panel... I have resinstalled the current driver... I have verified the F4 files.... if it's now unplayable on the EX ACT same laptop, monitor, settings as I played yesterday and the day before (and the day before and the day before etc. etc. etc) then all the words in the world can't describe just how pissed I am. 2000 hours of gameplay...
OFG, do you have any mods installed? If so, the update may have broken some things (apparently the F4SE doesn't work anymore).
As far as the content, from what I've been able to find out it's some Creation Club updates and support for pets. So nothing terribly interesting. No word on whether there are bug fixes.