graeme_p - 9:09 am on Aug 10, 2010 (gmt 0)
I am not convinced that this is deliberate because some of the scraper sites are scraping Google (Google Groups hosted mailing lists in particular), so Google are losing revenue.
That said, the duplicate content filters are not working well.
Almost everyone who has sent DMCA notices say they work, so the is a solution once you notice the scraper: DMCA notice to site owner AND host AND Google and Bing.
Now how do we spot scrapers? Copyscape charges per page, so it becomes really expensive very quickly ($250 a month per thousand pages).