That is pretty well put together video. In may indeed be real. Yet I do a lot with computer imagery, and so does my son and others. Given time I could see something like this being made. When it comes to video seeing is not necessarily believing for me. It MAY be in fact real, but because our skills have reached a level where we can make pretty much any image we want it is virtually impossible to discern a real video from a faked one. If that is faked it is really nice lighting, with some nice cloud particles, and a very nicely textured and modeled alien. Though it is definitely doable.

Now what is most interesting to me is NOT the imagery. It is the words he spoke. They seem very plausible.

EDIT: I do believe in extra terrestrials though. Time travel being their origin is certainly something myself and many others have considered before. Though I am weird. I am a scientist, yet I also believe in ghosts, and in the possibility of many cryptozoological creatures (e.g. bigfoot). So me saying I believe in extra terrestrials likely doesn't mean much because I believe in other things as well. At least until I see EVIDENCE that disproves these things.