Another two-day read. This is getting fun! (Well, okay...I think it was 2 days and I finished it in the morning; I couldn't put it down). (Update - actually, I do have a way to check... 1 day and 14 hours!)
Like some folks had said, (well, always say) don't watch the movie first or you'll read the book in Matt Damon's voice. Well too late. I don't know that I read the book in his voice, but I certainly visualized it like the movie portrayed it.
I don't know if movies are being truer to their novel roots lately or if I've just been more forgiving. (Or, going in movie-then-book order, perhaps I don't notice as much when things go missing) Considering the book was mostly written from Mark's daily log point of view and the movie was just one person talking to a log, that much couldn't really change. It's not like novels where you hear a character's inner-thoughts throughout the book which is incredibly hard to transition to film (looking at you, Ender's Game).
Anyway, yes - good book!