Vimeo definitely allows "machinima" movies....that is, movies made using game images/captures/video, etc....the difference is that Machinima means movies with
a Story or some sort, and dialogue, subtitles, voiceover narration, etc. "Gaming" videos are simply capturing gaming 'play' as the Game is played.
So, a video with just raw capture of a cockpit view in a Bf109 flying around (think First Person Shooter in a cockpit) would not be allowed.
However, a movie which tells the story of an historical battle or of an indivual fighter pilot's career or dogfights, etc, would be allowed. The latter would require some evidence of a screeenplay, editing, cinematography, post-processing perhaps with special FX, a sound track with perhaps original music, etc etc, etc.
Doesn't youtube still limit duration of video....to 10 or 15 minutes? Vimeo, I think, and also Blip-TV
definitely will host movies of an hour and more. For example, this hour-long IL-2 movie at Blip-TV
http://blip.tv/file/1217217