> What do we not know?
We have zero information about the vulnerability, other than that it allows unauthenticated access to AMT. One big thing that's not clear at the moment is whether this affects all AMT setups, setups that are in Small Business Mode, or setups that are in Enterprise Mode. If the latter, the impact on individual end-users will be basically zero - Enterprise Mode involves a bunch of effort to configure and nobody's doing that for their home systems. If it affects all systems, or just systems in Small Business Mode, things are likely to be worse.
> What should I do?
Make sure AMT is disabled. If it's your own computer, you should then have nothing else to worry about. If you're a Windows admin with untrusted users, you should also disable or uninstall LSM by following these instructions.
Otherwise we don't really own our computers.