Wow, what a depressing thread. Cloverfield was bone-fide genius filmmaking, probably one of the 10 best US movies of the decade. It's a crime that that the script was not oscar nominated (and no I'm not joking in case anyone thinks that...)
I've never seen a film play just as rushes (unedited tape) before. The device of recording over a previous tape was stunning, even using spooling back to watch something to believably create a gap for us to see what was there before. That's really imaginative storytelling. Also (like Blair Witch, incidentally) I had no problem with the characters - ordinary joes and joannas to be sure (which they needed to be for the premise to work), but perfectly believable and not annoying imho.
As to the handheld device, it's absurd to point to other classic movies which aren't handheld as if that invalidates a verite style. The camera style neeRAB to be a part of the whole - in this case there was no alternative. And, of course, plenty of classic movies have featured handheld camerwork either in part or fully.
Once could argue that its stolen 9/11 references were in bad taste, but personally I get the catharsis argument - facing your fears through pulp fiction.
I think Empire's original 5* review was spot on - they reinvented the monster movie and made it new again. I guess some people's expectations of what a monster movie should be precluded them experiencing this... what a shame.