From L.A. Times
The original writer of the script for I am Legend, Mark Protosevich, has just pitched a sequel for the film to Warner Brothers. I am Legend is based on the 1954 novel by Richard Matheson. The film will debut later this year, but it was ten years in development purgatory. With everyone from Michael Bay to Arnold Schwartzenegger trying to get it mobilized.
Details on plot for the sequel have yet to be released, and word is still out on whether the sequel will even be picked up.