When it first came out, I reported that I enjoyed I am Legend except for the change in the climax. I suspected the producers changed the ending to give it a more hopeful feel, thus betraying the entire point of the book.
Regarding the future DVD release of I Am Legend…
The movie will be released on DVD in two editions: a one-disc release, including the movie with four animated comics (“Death As a Gift”, “Isolation”, “Sacrificing the Few for the Many”, and “Shelter”), and other DVD-ROM features; a two-disc special edition that will include all these extras, plus an alternative theatrical version of the movie with a new controversial ending.