Happened to me too, both on my SP3 with Win10, and my home desktop on Win7 Home Prem.
This thread on MS Answers, also from earlier today, is the only other thread I've seen mention it:
h t t p : / / answers.microsoft.com/en-us/onedrive/forum/odstart-odinstall/this-device-has-been-removed-from-onedrive/180406f4-2354-4c1e-b533-ce79d1d8e13c
(haven't posted enough to post links, I guess)
I'm going to leave my files un-sync'd for now until I'm confident this has blown over...