I just ran into this problem today for the first time. Everytime I typed a single character the rainbow wheel of agony would pop up and I had to wait for about 8 - 10 seconds before I could type again. As long as I didn’t type things seemed OK. I tried relaunching, emptying cache, yelling at the computer and nothing worked. Everything else on the computer seemed to be running fine.
So for the first time since installing Mavericks I had to reboot my computer. It seems to be OK now, but I think there must still be some underlying issue in the new IDE.