I'm 36 hours into the game. I have defeated the bad guy, bought just about every property, completed the See the Future DLC, and gotten most of the achievements. However, any time I travel outside the area where my save is, I get hit with a massive slow down (5 FPS or so), my dog refuses to do anything, and weird things happen like chairs flipping around. I've searched around and the the only solution I've seen is to start over, which is a bullshit solution because it doesn't actually solve anything. I don't want to play another 36 hours to finish up the few quests I have left and I certainly don't want to play that long just to have it happen again. 
 
I don't know if they're related, but I ran into another glitch yesterday that has persisted. The main menu, but not the in-game menu, keeps screwing up. When it loads and I hit down to select continue (hey, developers, stop making the default "new game" when 99/100 times I'm going to be continuing, not starting over) it scrolls through all the options. If I hit up it scrolls back through all the options. Then it usually just gets stuck for 30+ secs or so, after which I can usually navigate normally again. I thought it was my controller at first, but when that's going on I can bring up the guide and navigate it just fine. Maybe it's having trouble reading my save file, which is partially corrupt, which could also explain the slow down. I hope not.
 
Has this happened to anyone else that was able to get around it and have the game start playing normally again? The menu bug I can deal with, the other one I can't. It's really making me consider whether or not I want to break the seal on my copy of Fable III.