We have a website that is about 10k pages. We have redesigned several times and have many redirects (about 2k). The redirects have been in place for more than 6 months.
Question - what is too many redirects? Also, I know the the big search sites will not like to have so many 404 pages at one time if we remover them all. However, do you think they see this as duplicate content even though there are so many redirects?