Yes, I did and a friend of mine also received the same notice.
Hello,
We're contacting you about order xxxxxxxxxxxxxx for Super NES Classic.
We recently learned that we may miss your delivery promise and apologize for the inconvenience. You will still receive your order of Super NES Classic. We are working hard to ensure you get this item as soon as it is in stock. You can track the status of, or make any changes to, your order under Your Orders on Amazon.com.
We hope to see you again soon.
Sincerely,
Customer Service
Amazon.com
I would worry about it, but they are not worded like the other Amazon backorder emails where they ask if you want to cancel your order and say "We will do our best to obtain this item". I've had a couple items do that where they sent 2 or 3 of these delay emails and then just canceled my order.
Also, they do flat out say "You will still receive your order of Super NES Classic.". I'm just hoping it's a delay of a few days rather than weeks or something.