What a waste of 2 hours and $15 bucks for what we already knew happened.
Right off the bat: Fuck the Shirley retcon from the condensed films. Terrible with a capital ERRIBLE. You negate a highly emotional (and fitting) climax to their story just to have a way to have "evacuated" Lelouch's body after Suzaku killed him at the end of season 2 and then she is on screen for all of 30 seconds answering her phone and talking to Milly.
With that out of the way, it was cool to watch the characters play their parts again on a big screen, but there was something missing in the shift to 2 hour movie from 54 episode series.
Shamna would have been a great villain if her Geass was kept hidden until the end. The time rewind aspect would have played really well if we got to see Lelouch or C.C. interact with it over a 8-10 episode arc. Wasting something like that on a 2 hour movie is bleh. Her brother was even more irrelevant, only serving insofar as to give Suzaku something to do for the duration of the movie.
Speaking of, did anyone else catch what her code did? Or was it her Geass that allowed her to re-wind time coupled with her Code allowing her to revive during the reset?
Along with that, the complete lack of use for characters like Rakshata was wasted potential too. Tohdoh and Chisa ending up married in the end credits was a nice touch.