Yeah there's A LOT of framerate issues in Fable 3. Especially with minigames.

I noticed this a bit too, but it was after I'd been playing for a serious number of consecutive hours. I booted it up this morning quickly before I went to work and it was fine. As others have mentioned though, frame rates have never been truly stellar in the fable series. I hope for Fable IV they decide to use a new engine.

i havent had too many issues. every once in awhile im sprinting and then slow down, but only for a second. 
 
then again, the only mini game i play is lute hero. im a beast at lute hero.

There's times where I felt like I was playing a Zach Snyder movie, slowdown, real-time, slowdown, real-time

The slowdowns are horrendous yet completely arbitrary, I've had hitches that lasted for seconds in empty fields, and perfect smoothness in huge battles with lots of magic and effects going on, I've had minigames work perfectly, or lag like hell forcing me to fail, I've had perfect smoothness for hours on end, and then sudden drops that made me think it froze. 
 
What the fuck is wrong with this engine, and will they ever fix it?

im a beast at lute hero.

Let's hope this doesn't have these problems on the PC. I played Fable 1 and that ran beautifully compared to the Xbox version, which if I remember correctly had slowdown issues as well. Fable 2 is unknown in comparison for obvious reasons, but I remember the framerate being really erratic and would slow downs just for shits and giggles.
 
You would think seeing as how this is a Microsoft published game, they would get this thing running as smooth as possible on the 360. Perhaps they imagined you will be so into them balls when playing, you wouldn't even notice the engine being a jerk. I know Fable 2's slowdown problems didn't totally bother me as I was way into the game so it was all good.

yeah there are loads of fps issues and lag.

"Perhaps they imagined you will be so into them balls when playing, you wouldn't even notice the engine being a jerk."  

Considering that the last game I played was Fallout: New Vegas, I haven't really been bothered much by the frame rate in Fable III.

I personally feel if they had gone with text menus they wouldn't have such performance issues.

I had issues with lag/framerate when holding hands with certain villagers.  If I went on a date or escort quest I would experience (at times) not being able to sprint.  I actually quit out of some quests to return later because it would have taken forever to tiptoe across a particular town.  I also had the slowdown issues during running, and my guess is it is related to villagers/monster pop-in.

I'm having extremely bad lag in the Co-op portions of not just Fable III, but Fable II as well. Is this because I hook up to Xbox live through wireless?