Paul did not join the cast of anything, since the movie itself is Paul. Nick Frost and Simon Pegg are the main characters, uber-geeks who stop off at area 51 after a visit to Comic-con. When they get to Area 51, they meet Paul, the alien voiced by Seth Rogen, who asks for their help escaping from the government. There are several other great actors on this project, including the just announced Sigourney Weaver. Chicago has seven cons still to go this year, 3 this month alone. This weekend is Torchsong, the Who/Torchwood convention headlined by John Barrowman. Next week is Duckon 18, and finishing the month is ZombieCon. You can see the full list at the Chicago Tribune gallery site, one con per picture. Finally, Borders has started its own SciFi blog, called Bable Clash; it will be interesting to see how it evolves.