Oh man, too many to count. For my first day and a half of playing, every stagecoach and wagon was fucked up, they were partly or half stuck in the ground and would bounce up and down making loads of noise. Pretty funny when you are playing poker and all you can hear is the noise of a wagon going haywire.
The most messed up one I saw was in Thieves Landing though, I stole a stagecoach and it was fine before that, but once I got in it bounced and lagged like crazy(I was offline), I drove it(barely) and half the horses wouldn't move, or they would separate and go opposite directions like they were wild. I kept driving though and I went over a pretty big bump, and when I did the horses shot straight up into the air and didn't come down. I wouldn't see them when I looked up. Now the ropes and stuff where still there, they were just completely vertical so it looked like the stage coach was a puppet. Hilarious when it happened, I must say.
That's about it for the glitches I think, there are some messed up random events though. I was wandering around the desert on foot at night before(role playing a man against the wild type thing, was killed by wolves in the end) anyway, was wandering around and I found a dead body of a man, and beside the body was a woman on her knees crying. I was expecting a, go kill the people who did this side mission, but I was stunned when the woman pulled a revolver and shot herself in the head. That had a huge impact on me, and I still think about it to this day. Was really powerful, completely stopped me in my tracks.