Profottballtalk.com is reporting that the Lions have traded RB Jerome Harrison and a 2013 7th round pick to the Eagles for RB Ronnie Brown. Brown will slide into the 2nd string role as soon as he is able to get the offense down. This trade makes tons of sense for the Lions since they are adding a proven every down back for minimal cost. The Eagles get a 2013 7th round pick and a player they traded for last year and then chose not to resign.
My guess is Brown made it clear he was unhappy with his role in Philly and the Eagles wanted to get something for him.