Here's the summation so far for the best horror movies from this millennium in my humble opinion. They're not really in any order. I have a hard time saying that one is better than the other.
Cabin In The Woods - 10/10 - best premise
28 Days Later - 10/10 - best zombie film made
The Mist - 10/10 - best monster flick
The Descent - 10/10 - must see
The Ring - 10/10 - great twist
Kill List - 10/10 - mafioso twist
Attack the Block - 10/10 - loveable
The Host - 10/10 - korean horror at it's best
Bug - 10/10 - plodding and itchy
REC, REC2 - 9.5/10 - super amazing found footage
Paranormal Activity - 9.5/10 - great twist
Time Of The Wolf - 9.5/10 - a hard realization
Let The Right One In - 9.5/10 - empathatic, better than the remake
Shutter Island - 9.5/10 - deep and dark
Mulholland Drive - 9/10 - a rare awkwardness
The Others - 9/10 - great ideas
Evil Dead - 9/10 - intense
The Conjuring - 9/10 - "true story"
The Loved Ones - 9/10 - edgy
The Crazies - 8.5/10 - dealing with morality
The Road - 8.5/10 - sadness incarnate
Orphanage - 8/10 - kinda drags
Trouble Every Day - 8/10 - wow
It Follows - 8/10 - stimulating
The Babadook - 8/10 - creepy
The Skin I Live In - 8/10 - what? no.
The Devil's Backbone - 7.5/10 - epic and sad
Sinister - 7.5/10 - creepy
Maniac - 7.5/10 - uber stalker
The Guest - 7/10 - "what if"
Kairo - 7/10 - tough
Insidious - 7/10 - strange and dark
Under The Skin - 7/10 - mysterious