This isn't going to be a clean transition.
It's not surprising that they're planning to use Freeman to help ease Angerer back into the mix. They like Conner and Freeman hasn't been working at that ILB position. Also, Freeman has been good, but inconsistent in the base defense. So there's not a clear case to be made for Freeman to start at either ILB spot. There's also a case to be made that Angerer won't stick in nickel packages right away. Moise Fokou has been decent in coverage and Freeman has some pass rush upside that Angerer does not. There's no clear financial / future incentive here either, as the three main cogs are all signed through 2013.
Expect a lot of rotation and shuffling in the first two weeks Angerer is back as the Colts evaluate the mix.