For the US? and Globally? I came across these off a quick google search:
Trail of Crumbs
The Mija Chronicles
New World Review
Paris by Mouth
Personally I am becoming more and more a fan of Street Gourmet LA as I live in LA and have experienced, separately but similar culinary discoveries in Baja and my vacations of the last few years have constantly taken me to Mexico, despite cartel wars, swine flu and anything else the Gods seem to throw at us after we bought plane tickets.