Yes, we received that letter as well. It was obviously junk mail, and I was about to put it in the bin when I noticed it was addressed 'To the lovely people living at [our address]!'
Curious as to which organisation would write something so nauseatingly creepy, I opened it. And then I threw it in the bin!
It is, of course, a commercial enterprise, as we can see from its backers. So anyone who signs up can confidently expect an increase in spam, junk mail and targeted advertising.