Cutts said that this update affected less than 0.1 percent of all searches and according to the Cutts Twitter account, this thing happened at about the midnight on Saturday.
There has been something I found in discussions from the SEOs that they have faced this update last month. However, Google insists that this was the first update for penguin since April 24.
The good news is that whether you were hit the first time or this time, is that you can recover. Google will continue to make more changes to its Penguin Algorithm; there should be plenty of chances to do so. Think about the panda update last year where Google had the same goal in updating its algorithm.