tedster - 4:48 am on Sep 30, 2011 (gmt 0)

I don't really like 404ing a large number of pages because I think it makes your site look broken.

The problems I've seen come from not removing internal links to the URLs that now return 404. I've worked with redesigns and redevelopments where WAY over 50% of the URLs were removed and it did not cause big issues or penalties.