First off I'm delighted Jackson is going to be involved, I was one of those who felt he was the only man for the job (not that that would have stopped me from seeing the movie). Its a huge sigh of relief as I think he will respect and maintain the spirit of Tolkien for The Hobbit as well as he did for The Lord of the Rings.
The worrying bit is the "sequel" business. I'm not aware of any hobbit stories set between The Hobbit and The Lord of the Rings so I'm concerned as to what story they'll come up with. Time will tell I suppose.
The two Hobbit films – The Hobbit and its sequel – are scheduled to be shot simultaneously, with pre-production beginning as soon as possible. Principal photography is tentatively set for a 2009 start, with the intention of The Hobbit release slated for 2010 and its sequel the following year, in 2011. Jackson and Fran Walsh will serve as Executive Producers of two films based on The Hobbit. New Line will manage the production of the films, which will be shot simultaneously.