Have those of you who own the lens found that the new firmware makes any IS jumping improvements? I reported the issue to Canon a few months ago, and was glad to see they issued a firmware fix. However, I am not really noticing any difference with the new firmware. Still jumpy.
I report issue to canon few months ago too!
For me, the jumpy image was 50% rate when i switched on the camera so very often. I did the update and a few turns on / power on the device without having any problem .. I will test this more asap.
If you still have the problem, could you send a video ?