I've seen so many little changes in the update the past few builds it would probably be hard to do that now. Most of us haven't seen the final upgrade process from 7/8.1 but so far it has involved 2 or 3 button clicks. Easiest OS install or update there has been.
I mentioned in another thread a pain point I think we will hear a lot about.
Most Windows 7 users do not have a Microsoft account, and while it is possible to install Windows 10 without one, it takes a few extra steps and you loose all the integration points.
They made it easier, but I still think it will be a major complaint point - again: