vero - 2:20 pm on Jul 13, 2009 (gmt 0)
Something similar happened to me. Suddenly no referrals from Google at all. I did two things. One, checked every external link and removed any that were slow loading, had gone dead, etc. The other was to remove some copy that had been added at the head of each page - it was fairly lengthy, so perhaps Google saw that as duplicate content. Also, I know G doesn't like changes in the titles of pages, but one word shouldn't be the issue. Good luck.