I have waited up to 8 weeks here in Chile to receive items from overseas. Especially if someone from Aduanos (Customs) has a peek. If Mexico is like Chile, most public servants are off for awhile over Xmas.

I wouldn't get excited just yet. I encourage people to ship registered mail to me in Chile, if not cost prohibitive. It only costs me $1.50 more to add registration when I send from Chile to overseas, money well spent.

-Oke