I suppose it depends on what one means by it. There seems some debate as to whether it is a movement or more of a label from outside... a bit like the New Wave in sf in the 1960s-1970s. Or, for that matter, what writers one includes in this category....
At any rate, though Mieville doesn't quite hit me the way he does many, I admire his abilities and his imagination. At his best, he's damned good, frankly.
Ligotti, though somewhat uneven, is a fine writer -- one of the best and most disturbing working, as he creates a genuine aura of nightmare that is rare at any time in the field. Highly recommended.
Caitlin R. Kiernan sometimes annoys me with her merging of words (which come off to me at times like a particularly disastrous train-wreck) that can yank a reader out of the text... but that's a minor complaint about an otherwise very fine writer in the genre. Another who manages to subtly displace reality in a very nightmarish fashion, all on a very quiet level....
M. John Harrison I'm more familiar with as writer of sf, having come out of the New Wave movement of which I remain very much a proponent.
Several of the others I've either read nothing by, or so little that I really haven't yet formed an opinion....