I recently got one of my contributions deleted by Tripadvisor, and mailed them to ask what's going on.
Helpdesk replied:
"We are sorry, but we list Airline restaurants so long as they are accessible to the general public and not for departing passengers only. We are sorry but this is the policy we are implementing."

What a shame! Restaurant reviews for air travellers is exactly the type of advice i'd expect from a site calling itself Tripadvisor. I guess i'll have to resort to Foursquare when in in transit next time.