(since antirealist already beat me to the first...)
Oddly, I happen to be the person who asked Michell why he chose to use a hand-held camera on Saturday, and his initial response ("Why not?") was a bit flippant, but at the same time, I'm guessing the filmmakers weren't intending to give anything other than glib answers to the puffball questions they were expecting. (When asked if they felt the film perpetuated the negative stereotype of the mentally ill being violent, director Michell dismissed the allegation out of hand before Rhys Ifans stepped in with a quick-hit one-liner about being "completely sane, but I'm feeling a bit violent about that question." That should do it for intelligent discourse at THIS Q&A, thank you...)
The camera-work is a bit distracting, not necessarily because it's hand-held but because the reason for it -- which Michell did say was to represent a first person POV -- is so obvious. In particular, there are a few scenes in which the camera sneaks around behind walls and windows to catch a better view of the characters that screams "you're being watched," which generally sums up my main concern about the film: it telegraphs almost everything.
For a psychological thriller, it isn't nearly as taut or unpredictable as it needs to be. It also lags notably between plot points, content to bleed off any steam it may have picked up from a previous scene. Part of this problem could be caused by the trailer's reliance on exposing nearly every twist in the film, and part of it could be on the film's overuse of "thriller music" that, in the cut I saw, nearly overpowered all five senses every time it appeared in the mix.
However, the acting is generally impressive, yet understated. Daniel Craig does a wonderful job at portraying the complexities of a rational man who comes unhinged in the aftermath of a bizarre accident and the resultant stalker he's burdened with. And there was at least one twist that made me jump, so all is not lost on the tension front.
Last thought: I was stunned by the film's equation of homosexuality, theology and mental illness. I'm not sure what exact conclusion it (or the book) is trying to come to, but I'm guessing the post-screening Q&A wasn't the place to bring it up...
