It looks interestingly creepy, but I do think that juxtaposing the "real" footage against the actor's scenes reveals that the supposedly actual footage is way creepier than the "reenactments". This could end up undermining it, as it may not hold up under comparison.
If you can't tell by now, I'm not entirely convinced by this story. Its foundation seems to be thin. I suspect it's a viral marketing hoodwink with a bit of stereotypical, X-File-ish UFO stuff we've all been exposed to.
Hopefully there is more to the actual story than all the "real footage" hype, but as it's a Milla Jovovich pic, I remain skeptical. The trailer is sufficiently creepy, though.