Zagat, best known for its reader-generated restaurant guides, also applies its methodology to the airline industry. Latest survey results shout "swell job" to Midwest Airlines, known for their freshly baked onboard cookies, and Virgin America, a newcomer, who delivers top-notch onboard entertainment to all passengers.Meanwhile, the news is grim for other airlines. Since Zagat began covering airlines in 1990, only Continental and Southwest Airlines have improved in reader survey results.