From the first post what should have been in it and came under Space:
In addition, the program looks at the way Dune and The Mars Trilogy embraced the challenge of world building and discusses the appeal of the beaten up ‘dirty space’ of Dark Star and Firefly. From the horrifying scenes of Alien, to the epic spectacle of Star Wars, this is a journey to the stars and the alien encounters that await us there.
They changed both the title and the presenter so it should be no real surprise that they also changed the content. Having said that Nathan Fillion's was still in their publicity photo as shown in the first post in this thread.