Update: Many of you in the comments along with @GoogleMexico have confirmed that navigation went live earlier today. Congratulations!
Google Maps Navigation(Beta) ahora disponible para Android en México. Descarga la versión más reciente en Google Play: goo.gl/DgNq8
— Google México (@googlemexico) November 28, 2012
Original story below:
It doesn't mean anything yet, and we'd be hard-pressed to tell you when it will mean something, but if you were to take a look at this help file listing countries where Google Maps Navigation is available, you'll see a relative newcomer to the crowd: Mexico.