Sorry Zin, Prometheus is shit. I'm pretty sure even Ridley Scott has said it really wasn't how it should have been (similar to how Spielberg and Shia later admitted that Crystal Skull-fuck they gave audiences was not up to snuff). I have some hope they'll try to improve things with the sequel.
Has fucking nothing to do with being an Aliens fanboy either (I do prefer watching Aliens over Alien, but both are good and the original was better in many regards). I couldn't give a shit less about the franchise to be honest (can't really figure out the hardon people got for that recent Alien game with the horrible scripted Alien, or why people were so mad about that previous Gearbox Alien game), so I don't care about it trying to flesh out that universe or any of that nonsense (although it was pretty much the only interesting part of Prometheus, too bad they subsequently decided to wipe their ass with everything after the setup).
The movie had horrible characters. They squandered excellent technical aspects on some of the dumbest fucking plot actions I can fathom. The decisions made by the characters are in line with what I expect out of some no budget trash horror movie. It could have been so much more, as they had the talent to make something really good, but then just blew it on such a pointlessly stupid script. Much like that second JJ Abrams Trek.
I mostly agree with the OP but I don't about District 9. It is not some masterpiece of science fiction but it is fine for what it is. I think he's buying too much into the Apartheid analogy and so he's taking the movie as some high minded thing when it really isn't that (I can understand why he'd feel that way though). I feel generally Blomkamps stuff is a bit Wachowski-esque in that it tries to act high minded but falls flat, but he sets that stuff generally as more of a backdrop and then realizes a somewhat interesting story through it, although it ultimately fails to live up to its potential. Think of it as modern version of those 70s sci fi movies, where they're not really that good, but they're still somehow compelling enough to watch but ultimately leave you feeling empty of any real poignancy.
I also don't get why he's even commenting on Grandma's Boy? I have never seen anyone act like that was some amazing movie, but I've seen him complain about it being loved (by whom I have no clue, I've barely seen it ever mentioned). It had some chuckles but has serious problems as an actual movie goes. No one is considering it a classic or anything.
Oh, not sure if it there was much discussion about it but saw it mentioned, but I thought Skyfall was pretty bad, largely due to the villain. I remember reading reviews on Netflix of some people that think it might be the best Bond movie of all time and largely because of the villain. The rest of the movie was competent but not in any way truly thrilling. I'd actually have said it was utterly forgettable if it wasn't for the "really?!" feeling I got from how crap the villain and just about everything directly involving that character (that awful computer hacking chase scene for instance) was.