deadsea - 12:59 pm on Mar 21, 2011 (gmt 0)
Having tons of really bad pages did *NOT* hurt sites in panda. I run multi-million page web sites. None of them were hit by the Panda update. They all have really good pages, but also tons of pages that are *REALLY* poor. User profiles with no content, inane forum topics, pages about small towns with no content, etc, etc, etc.
Having tons of poor pages itself is not going to hurt you. Not having good pages, or passing too much internal pagerank to poor pages would seem to be a more worrying signal for panda.
Our sites always have that message in webmaster tools as well. We've been ignoring it for years.