davidof - 9:44 am on Mar 29, 2012 (gmt 0)
This is what I saw on a couple of domains.
1. with lots of backlinks and good PR, not too much change
2. newish domain, few backlinks, good SEO. 50% drop which continued for a couple of says, now slowly climbing back up about 15% down.
I suspect some of these algo changes take some time to settle down as the site is reindexed under the new algo.
Of course what I've seen may be entirely random but fits with some of the above posts. I only checked in here because I thought "whoa, what's happening".