As a long time lover of the book and having just seen the movie last night (hey, I'm 38 and have a kid, I can't jump opening nights anymore), I had a couple of points I would like to share after having read many of your comments.
On the pacing of the book; I believe that the author was purposeful in keeping these slow, dragging sections as he did. Every time the pacing slows a bit, the character is fully engrossed with near superhuman focus on the event or problem at hand. The rest of his life flys by in a blur of tedium that never ends. Even to the fact that the only recourse he has against the decline of his mental/emotional state is to drink, hate himself for drinking and, inevitable throw his half-empty glass against a wall. But, even this becomes tediously repetitive, showing that he was really getting no where with maintaining the status quo that his life had become. Yes, he must focus so acutely on the dog because it's the only living thing that has come into his world. And by the point it arrives, he's so used to focusing on the study of minutia, he makes a study of the dog's responses as well. The part that keeps these scenes moving is when his emotions break through the facade of his controlled existence and he remembers what it is to be truly human...and to be truly alone.
This, for me, was the only saving grace for the recent movie. Will Smith's attempts to show us a scientific man on the verge of losing his mind was brilliantly done and I couldn't think of a better man to play it. Oh, sure, maybe Tom Hanks, but then the dog would have been easily replaced by a volleyball and the scene would have lost all its meaning. Now, if Wilson had begun to grow fangs and attack Tom on the raft, that would have been AWESOME. But, I digress. Of the film, I am Legend, the monsters were rediculous, even the name they give them is cartoony, which pretty much sums up what I thought of the CGI, but they were still better acted than the woman and kid. Okay, I can't blame the kid, it must be hard for a tot to sit there while Will Effin' Smith is quoting Shrek verbatim like an idiot savant. I even started laughing uncomfortably in the theater. I don't know how that kid managed it. (might make for some interesting outtakes). Even with the beautiful acting by my fellow Philly brother, the movie was an overall disappointment, simply because they went for, what I consider to be, the cookie-cutter ending instead of the more thoughtful end the book presented. The fact that, even after the end of the world, the mutated, viral, maybe even vampiric survivors would naturally attempt to create a civilization with rules and structure to safeguard their survival and that civilization would come to fear and hate the previous civilization that caused their misery with such passion they would hunt down any icon of that age, including its last surviving member, makes the human animal the monster, the villan of the piece, instead of having the whole, "we few survivors will live on due to the sacrifices of one man". They had a chance at a truly brilliant ending, but chickened out, and for that, I cannot forgive them.