I recently received an email from a McRib fan in Mexico. The email informed me that the McRib was soon to arrive in Mexico, and gave a link to the Mexico McDonalds Site. I took a look, and sure enough, the McRib is going to be there soon (if not already). Watching the video(and if I translated the fine print correctly), it also appears that the McRib will be in Mexico through the start of April! Sounds like I might be getting ready for a trip across the border sometime later this winter.
Thank you for the tip Rodrigo!