Another thing you can do, when you know another site has something that relates to you, is to bookmark that external page, using a site that the search engines visit regularly. For example, If that external page is new and it is a useful page about an iphone App, you could submit it to Digg. That should get the attention of other diggers and the search engines. You would be boosting the power of the other site and the link to your site, and getting the search engines to find it.

I don't do that often, but I have done it a few times, and I think it works.

Thank you for the fast response, Alex.

They are character for character exact matches, both with a trailing slash

http://domain.com/

All other variants are 301 redirected to that url,

except uppercase/lowercase, which gets a 404 error response.

The system says I have two duplicate page titles. The page titles are exactly the same because the two URLs are exactly the same. These same two identical URLs show up in the Duplicate Page Content also - because they are the same.

We also have a blog and there are two tag pags showing identical content - I have blocked the blog in robots.txt now, because the blog is only for writers. I suppose I could have just blocked the tags pages.