I am a big fan of the original novel by Matheson. The story of the last man on earth facing a world of vampires was well written and had a great ending. It had been in development for quite awhile after having two previous attempts at bringing this story to film.
What makes the book great is how Neville goes through his day to day routine and how that slowly breaks down. It helps that each night people who he knew call out to him trying to get him outside. I won't spoil the end of the book here, but it it the ending that makes the book in my opinion.
I'm assuming that if you are reading this that you have seen the movie or are familiar enough with it that I don't need to explain everything, and not worry about giving spoiler warnings.
As far as the Will Smith version goes, I have to call it a missed opportunity because so many things were missing that it spoiled a great opportunity. Here is what I mean:
-A virus instead of vampires- Not a huge problem, but the infected were never really explained well. Are they savage creatures or some type of new society? Pick one. Savage creatures don't keep dogs. Straight up vampires would have worked much better and needed less explanation.
-Survivors- What made the film work for the first 3/4 was Smith by himself. Being the last man on Earth is what drives the whole story. Is he going crazy? Are his chances for survival slowly dwindling?
-The ending- Do I have a problem with his death? No. I have a problem with the lady's monologue at the end wrapping everything up in a nice box. The book does not end in a nice box and that is what makes it powerful. This movie could have left us pondering what the book does. What does it mean to be human? What does it mean to be human with other humans? At the end of the book I was going "Wow." Many great conversations could be started from a book like that. At the end of the movie, I missed my $7. The movie was ok for the first 3/4. But the end was its end.
I would give it 6/10