I just got it, and the email address it went to is an address I ONLY used to register with KDP - literally the only time that email address is used is for interacting with KDP, and there are no possible links between it and any of my actual pen names.
So there are only two possibilities as I see it:
1) This email is fake, which means someone has gained access to Amazon's central KDP database, as that's the only way they could be mass emailing all of us to our KDP registered email accounts.
2) This email is legitimate and Amazon is actually asking self-published authors to email blast Hachette as part of their ongoing negotiation tactics.
Quite honestly, I'm not sure which possibility disturbs me more. That our info is that vulnerable to an outside hacker or that Amazon actually thinks petitioning authors to email their competitor on their behalf is a worthwhile strategy.
If the latter, good lord this has gotten ridiculous. As Patty said earlier in the thread, Amazon is not our friend. They are not negotiating with Hachette on our behalf. Its entirely possible that Amazon emerging victorious from these negotiations will be the better for authors than if Hachette 'wins', but even so, that is entirely incidental to their true goal in these negotiations - aka protecting their bottom line. They are not crusading for a better future for literature, the arts and authors everywhere, and quite frankly I find recruiting authors into their negotiation tactics under that guise to be actually kinda insulting.