We run an ecommerce site which had a top ten position. Last year we believe we were penalised by google for "spaming" (mostly due to lack of experience). We think this was down to high keyword density. I have had a look around and can not seem to find a definitive answer on what is the optimum density. Our site is sitting at around 11% for the main key word.
We are currently reviewing all our content and a looking for some guidance as we really want our top 10 position back.
[edited by: encyclo at 1:07 pm (utc) on Mar. 10, 2008] [edit reason] no personal URLs thanks [/edit]