I wouldn’t say that I hated Keanu Reeves – but I’ve never seen him deliver a performance that knocked me out.
I’ve heard that he did a good job in Thumbsucker, but I haven’t seen it.
I have seen him in pictures that he didn’t stink up. I thought he was adequate in The Matrix. He was fine in The Devil’s Advocate. (That movie’s problems weren’t in the performances; it had a weak, weak script.)
He just has a limited range, and an unfortunate history of being horribly miscast, so that when he does stand out, it’s for all the wrong reasons.
I really want this movie to live up to novel, so I’d ideally have liked to have seen the role of Arctor go to a fecking brilliant actor. I’m pretty much reconciled to Keanu as Arctor now, though – and fairly optimistic. It’s not nearly so much of a stretch for him as something like his best-forgotten Jonathon Harker was. I think he’ll probably be watchable as Bob Arctor, and even have some hope that he’ll surprise us with something well beyond his usual performance. To be fair, it seems like he’s often either given something entirely beyond his ability to carry off, or something that gives him virtually nothing to work with. Maybe this role will hit that sweet spot at the apogee of his capability.
The one thing in the trailer that makes me a little bit apprehensive is his delivery of the line, “You mean the two hemispheres of my brain are competing with each other?” I’m trying really hard not to let that worry me too much, though, because sometimes lines that appear weak in a trailer work perfectly in their proper context – and he is supposed to be brain-damaged, after all.
At any rate, the rest of the casting is flawless, and Keanu’s approximately the right type. It might work. On the other hand, this is the same casting director that selected Keanu for John Constantine. Maybe he just has something over her. 
Like I said, I have extremely high hopes for this movie. Philip K. Dick was, IMHO, one of the best and most influential writers of the 20[sup]th[/sup] century, and the horrible degree to which his work has been misrepresented on screen so far is really frustrating to me. So far, films that are directly based on his work have been either appallingly bad, barely resembling their sources and opting to substitute tired cliche, or (less frequently) successful in spite of their tenuous connection to Dick’s work. Blade Runner is an excellent film, but only uses the basic plot of Do Androids Dream of Electric Sheep, for the most part discarding (or barely acknowledging) the most interesting elements of the novel, and introducing a radically original stylistic approach.
So far, the most faithful adaptation of his work has been the French-language adaptation of his non-SF effort, Confessions d’un Barjo. (Confessions of a Crap-Artist.) Even there, the protagonist is a strikingly different character from Dick’s self-deprecating autobiographical figure. (Quite apart from being, you know, French.)
With the exception of Blade Runner, film adaptations of his SF have stuck to his penny-per-word pulp-era work – which are of stand-out quality for the pulps, but barely hint at the full flower of his genius. (Sorry, gushing.)
It’s bizarre that (so far) the films that represent PKD’s influence on the field the best all started with entirely original scripts.
For the first time, we’re going to see one of the books from his peak period closely adapted. I’m really hoping that it does well, so that producers might find the balls to take a chance on something like Ubik; Flow My Tears, the Policeman Said; Time Out of Joint; or The Man in the High Castle, instead of pussyfooting around with the “safe” (and not-nearly-as-interesting) stuff.
Don’t get me wrong, that wasn’t meant to minimize his ability, I recognize his talent. It’s just that, in addition to his talent, he has relevant personal experience to draw from. I think it’ll help. Winona, too. Woody Harrelson has already proven that he can play this sort of role with pathos, humour, and authenticity.
Rory Cochrane is a perfect Freck, too – a more comic druggie that’s mostly managing to hold it together, if not exactly excelling in life. I can totally see him running around in the opening scene, frantically collecting his friend’s meth-bugs in a jar. That freaked-out, anxious look of his is perfection. Or, (if it’s included, which it damned-well better be) the scene where they’re trying to work out what’s wrong with his ten-speed. (Treading carefully to avoid spoilers, here.) For the parts where things are still (darkly) comic, Rory Cochrane is brilliantly cast.
I’m ambivalent about it. On the one hand, it’s frustrating because I’ve been anticipating it for so freaking long it hurts. On the other hand, I’d rather they delay its release than compromise with the quality – and besides, a July release is actually better, in some ways, than a March release.