The Peabody was posted today when I visited for the Insurors of Tennessee convention.
The signs appear to be gold-plated plaques. They contain proper verbage. They are on the sides of the walls, just inside the first set of doors at the main entrances.
However, the Bell-boy entrance on the side was not posted, and that was the entrance I used today. This was my first visit to the Peabody, and I found out the place was posted as I left a couple of hours later. I know the rule, so I checked other entrances. They all seemed to be posted, but for the bell-boy entrance, so I got lucky.