Mike writes to us on Virgin America’s maiden day of service to complain that his discount fare vanished after he signed up for Virgin’s frequent flier program. Mike and his girlfriend tried to buy $44 tickets from San Francisco to Los Angeles, but after signing up for the frequent flier program, the fare jumped to $79. Though Virgin has invested in a state-of-the-art in-flight entertainment system, from the looks of Mike’s letter, they haven’t invested nearly enough in customer service. Mike writes: