I don't know if this affects anyone other than me, but we had an issue right around 100 in an MP head to head campaign. We'd been religiously saving and sending the save to the other side and had avoided most de-sync issues - only a couple reloads and we never had to go back more than a turn. My side (Shimazu) had taken Kyoto three turns previously, and when the turn was supposed to roll over and congratulate me on becoming Shogun, instead the clan indicator continued to read 'Wako pirates,' but it came up with the news list, construction report, etc -- though no movie saying 'yay you're shogun now.' Also, when I went to move the mouse, graphical corruption started happening all over the place, and the game became unplayable.
We went back a few turns, but it continued to happen on the 4th turn after taking Kyoto. This did not happen in a cooperative campaign (which was with 1.0, though) nor does it happen in single-player -- there are no video driver issues.
I was able to work around the problem by quiicksaving right at the beginning of the 4th turn (even with the graphical artifacts), quitting to the main menu, and then resuming from that quicksave. We were able to play to completion.