Google just getting messier and messier - if I change the settings to show 100 search results per page instad of 10, I am getting dozens of pages from the same domain for pretty much 90% of the searches. Is this local thing or are you guys seeing the same? Searching for "naked"....
As for the penguin update, I don't think the Google dudes know what they are doing. It wiped out thousands of legit sites along with the ones with dodgy links; then again, even now you can build thousands of spammy links and rank well....
.