Don't Look Now! Good Idea Alert!
I'm not entirely sure what they're going to do wit the book, but the biography posited that Houdini was actually a spy for Britain and that he was once asked to be an advisor to Czar Nicolas II over in pre-Communist Russia. I guess that job went to Rasputin, instead. (And thank God, otherwise, Rasputin would've never come to prominence, and Eddie Murphy wouldn't have been able to name his Norbit character Rasputina. She'd be, like, Houdinia). The book also asserts that Houdini had it in for the spiritual movement -- he thought spiritualists were con artists, which may have led to his death.
The movie, which will be written and directed by Jeff Nathanson (he wrote Catch Me If You Can and Indiana Jones and the Kingdom of the Crystal Skull, as well as the upcoming Milli Vanilli biopic (for reals)) will most likely ignore much of what's in the book, as they are taking an action-adventure approach to the story in the vein of Guy Ritchie's upcoming Sherlock Holmes, with the hopes of launching a franchise.
You could do worse than a Houdini franchise. And now the race is on to find their Harry Houdini. Ryan Gosling, please.