walkman - 5:55 pm on May 1, 2011 (gmt 0)
Those reporting higher number of 'improvement' I think depend on a few pages for a large share of their traffic so you get a couple of keywords ranking (again)and via! The same when you lose them though.
I'm killed when I get a site-wide effect. I am only comparing them to total traffic patterns, Bing and Yahoo referrals and by scanning the referrals. Most good referrals are gone, some not but traffic wise it's a joke. Total traffic from post Panda1 is down by 20-30%, but since a nice share may account from one particular page /section I don't mind it as much provided I get those other referrals.
None of the changes seem to matter to Google, smacks of xx day penalty and then we'll see if you changed what we want you to change. Things are very unstable though, I get spurts of amazing referrals for 5 minutes and then...