Yes , they are making a movie adaption of the books. I met Lauren Kate when she was in Australia and she said that the rights to the films were bought by Disney and that the script for the film has just been finished. No one has been officially cast, however there have been several rumours (thanks to IMDb). Also, the film is set to be released in 2012 and will be directed by Saul Cajacuri.
I'll give you the link to the IMDb page, however any of the cast that is listed on the page is not official as yet, so they will probably change.
Okay so people say the movie is coming out in 2012 and all these random years but disney finished the casting on 31-1-13 and the Hollywood reporter posted "looks like the fallen movie by Lauren Kate is coming to cinemas " I did a bit of research though that and it coming out in late 2013. To early 2014 but casting list is coming out in a few months so get excited all fallenatics like I am ! Hope this helped :D