Does anyone think there will be an automatic update from 2-3? Or as the file structure is different do you think it'll be unlikely?
As far as I know, there are no plans for an automatic update from Craft 2 to Craft 3. I'd suggest following the instructions from the docs to perform the update manually: https://docs.craftcms.com/v3/upgrade.html
Not going to happen. There is a multitude of reasons, but the biggest one would be breaking changes, including templates. Allowing an auto-update that would likely break the site would be reckless.