Facetime "WORKS" in airplane mode! Duh!!

So i read an article in engadget regarding a man making facetime in the airplane using the plane wifi! That was totally cool. So i was wondering if he had any cellular signal to make it work and i've been trying to find a topic regarding how to use facetime (i know how to do it, but i wanted clear instructions and technical knowledge on how it really works)

Anyway, Facetime "works" on airplane mode. Period. I've tested it with two iPhone 4 with wifi on and it work!

It might be old news to everybody else, but i just figured it out now. Not sure about how video calling works on other phones and country, but i know that some still require some sort of cellular signal (3G) to make it work..

Okay now back to the "iPhone trash talking".. Lol