Sean Penn & Matt Damon cast in Harvey Milk biopic

Gus Van Sant has attached Sean Penn and Matt Damon to his long gestured biopic of openly gay 70's politician Harvey Milk who was gunned down by Dan White, a fellow electoral supervisor. This seemingly would now put the director ahead in the race to bring a Milk biopic to the big screen, as Bryan Singer is still shooting his Valkyrie movie and is not at the stage yet where he can make this kind of move on his next project. If things go as planned, Penn would be the politician Milk and Damon would be the guy who guns him down and it would mark the first time the two acting heavyweights have ever worked together. A December start date in San Fransisco is tentatively planned with a script from Big Love writer Dustin Lance Black being approved by Groundswell Productions who are financing the flick. The shaky start date which is not set in stone may effect Damon's involvement as he has other irons in the fire with The Fighter and another movie with Paul Greengrass titled Imperial Life in the Emerald City. So what does Singer do as a counter-move? Does he give up on the script written by his Valkyrie & Usual Suspectsscribe Christopher McQuarrie and tell Warner Brothers Independent that they were beaten to the punch (or will the studio force Singer into scrapping it for this reason) or does he go on with the project regardless? source - the hollywood reporter