Several airlines recently started offering Gogo in-flight broadband service on select domestic flights, charging users $12.95 for cross-country flights, and $9.95 on flights of three hours or less. However, an early problem has sprung up: airline attendants are complaining about passengers viewing porn, leading to a debate over whether these services should see content filters. While American Airlines has opposed filters, Delta says they'll now block inappropriate websites -- though knowing the unreliability of filters, it may not completely solve the problem.