Well Jesse B's fits my own feelings as to what the film is going to be and it does chime with my biggest worry from Prometheus, that the editing will be a mess in whole sections of the film.
Matt DeGroot's appears to be a Prometheus fanboy complaining about other fanboys disliking it so much that Ridley moved away from the 2001 aping aspirations seen in Prometheus.
I think people may have to come to terms with the fact that Ridley never intended to properly answer the "origin of life" questions, I'm not entirely sure what truths the films could hold with any gravitas. Maybe it's best left a mystery? Especially in movies based in a universe which are more concerned with the realities of there being a "perfect" hostile Alien creature.
From all the available evidence it seems Prometheus was a vehicle to set up the black goo, David's character, putting David in the position of being in possession of said black goo and maybe a bit of "what does it really mean to be human" in regards to how autonomous David was.