It has been open for a few years now. As of March 29, 2008 you still can not turn your vehicle stickers in there. We turn our's in about 17 miles east of Sonoyta on MX 2.
Chrispy Hubby and Ms. Mckenna
2002 Discovery 2003 CRV Winter Lo de Marcos/Summer San Diego
Unless something has changed, you can not get a Visa there and they will not issue a Vehicle Sticker without a Visa. You will be sent to the Airport and pay extra/fine/bride along with the normal fee. Our friends who were traveling with us had to pay an extra 1000 pesos and they wanted 1500.
rocmoc n AZ/Mexico