I've noticed that if you run past tons of monsters (like when you're just trying to get back to a boss), you can run into some low fps problems. It hasn't affected me too much, but it would be nice to have a smoother fps overall.
I'm mainly hoping they patch that invis ring so I can lock on to people. Seems pretty cheap. Someone said the no lock-on wasn't intentional, but that's just hearsay.