I'm not trying to be an elitist, but some of those films barely qualify as horror (Cube is science fiction, dudes) and are not that great. There's a difference between guilty pleasures (which, unfortunately, most of horror is) and legitimately good films.
There are indeed a handful of great B-Movies, like Drag Me to Hell, The Frighteners, The Mist, etc. All films I have enjoyed, none of them I'd call really good horror films. Genre fans are also predisposed to like this type of stuff, and I think that you really need see what appeals outside our niche to determine quality.
I mean - heck! - if I made a list of modern stuff I love to watch it'd probably include stuff like the aforementioned titles and Cemetary Man, From Dusk 'Till Dawn, Frailty, New Nightmare, Bram Stoker's Dracula, Session 9, Audition, Let the Right One In, High Tension, Dead Alive, Slither, Arachnophobia, Needful Things, Stir of Echoes, Event Horizon, Shaun of the Dead, Funny Games and probably a bunch I can't name.
Can I sneak Army of Darkness in?
Now, remove the foreign films and limit it to the really, really great stuff (that people will reference decades from now) - how many of those films survive that criteria?
I think you have to include stuff like Scream (regardless if its a satire) and The Ring as true representation of horror in the past two decades. It's been a pretty wretched time for horror.
Saw pretty much set the tone for this decade, which I felt has seen the shift of true horror leave American shores to the Pacific and Spain (Shiver was better than half the garbage released stateside).
'tis a shame.
Also, I still contend that The Ring is an American remake of a Japanese film adapted from a book that ripped off an American film (The Changeling).