I have a memory problem. I can read a novel and thoroughly enjoy it, yet I can often recall none of the details of the plot a year later. I also tend to do things like forget my girlfriend's birthday (I know yours is soon, Lu!) but I'm not sure if it's the same flaw in my brain. At any cost, I read Mystic River a few years ago but never got around to seeing the film, despite it's generally rave reviews. I was quite proud of myself, therefore, when about 10 minutes into the film I remembered all the plot twists and details from the novel. I won't spoil them here, but it made me feel like I'm not senile yet.
As for the film proper, (this is trite, I know) it wasn't as good as the book. It's not bad for an adaptation, but it loses some of the emotional grittiness of the novel. The Boston accents that everyone affects are really atrocious (Laura Linney actually sounds Australian), but I was generally impressed by the acting (especially Tim Robbins). Altogether a worthwhile flick, especially since they mention the Cantab within the first 10 minutes. Pickin' Tuesday anybody?