Bill Murray Talks "Ghostbusters III" With David Letterman

I've been hearing for years now that there is supposedly going to be a "Ghostbusters III" movie... for years now! Recently, as in this year, the chatter on the internet about this possible trilogy has been been getting much louder and appearing to be much more of a realistic. Hell, it's even already on the IMDB website for release in 2011. And then just last night on David Letterman, we hear from Bill Murray...