The mainstream wine media may not pay much attention to it, and the three-tier system may consign it to retail and restaurant oblivion, but over the last couple of decades, regional wine has rooted itself in all 50 states. There are 2,765 wineries in the 47 states that aren’t California, Washington and Oregon, according to 2010 figures compiled by Wine America — almost as many as are in California. Regional wine’s growth has been spectacular; there were just 217 wineries in 34 states in 1975.