As of this afternoon I'm seeing major improvements for the 20-30 phrases I usually track. One in particular which I've never been able to get above position #40 is now #6. I'm nervous that G is just showing these results for me even though I logout of Google before trying them. I'm not seeing significant increase in visitors likely because my 1000's of long tail searches may not have improved (yet).
ps. I was hit by 35% on Panda 1 and another 15% over the next several months gradually.