I think it's a great poster whether fan made of the real deal. I've got to say I think this is probably the real thing for a few reasons (some have already been touched on by people).
Firstly we know this is a dark movie and most of it is the fall of anakin so his face makes sense.
Secondly they wont want to give away to non star wars types a grevious poster yet....I think they'll save that for the second teaser trailer at the earliest, that face will make a big impact on people that aren't big star wars fans. Is it just me or does the background in that poster look sort of 'deathstar-ish/ destroyer-is'?? (wow I invented new words..PMSL)
Got to admit though that people are gonna be pissed off if they push the Vader angle in the build up to much and he's only in a very short time! That alone could get the film bad reviews.
It seems to me of late that the way lucas is handling things with the whole franchise in general it's almost as if he's ashamed of these movies. Not only does he say he wont make any more but if rumours are correct [certain I read a quote at some point but I can't find it right now] the story of EP3 will make it nearly impossible to make any more movies BY ANYONE! Thats as near a direct quote as I can remember...
BTW anyone got any ideas when the next web doc is due out?
Wayne...