I just verified this today. While my Windows 7 machines have the proper registry entry, my Windows 10 laptop does not.
Everything is updated, and I expect to get the Meltdown / Spectre patches from Microsoft for Windows 7 on patch Tuesday 01/09/2018.
I expected to be able to install the patch for Windows 10 today, but Windows Update claims that my system is already up to date.
ETA for a fix?