This MOGH/ChipGuide listing says this new Plaza (downtown LV) $5 "50th Anniversary" LE chip was supposed to be released a couple of months ago.
I assume it's on the tables and/or cage now, as Ricky's new issue service is listing it as available.

Was it announced here? I don't recall it, but may have missed it.
Anyway, looks like an interesting one to pick up during the chip show.