Just picked up a 10-18mm for my sister-in-law, who is getting ready to head to Europe. I noticed in the instruction manual that it says the image stabilizer only works on the EOS 7D and only at 18mm. I was not able to hear anything kicking in when I tested the lens on my 20D at very low shutter speeds. I haven't seen this limitation mentioned in reviews. Am I misreading this? If not, folks should really know about this before replacing a 10-22 and thinking they're getting image stabilization.