A WebmasterWorld thread is reporting either a somewhat widespread glitch in Google Webmaster Tools or some sites that are having issues. I am personally able to validate the issues, so let me show them to you.
I logged into Google Webmaster Tools, clicked on "Diagnostics" and then on "Content analysis" and then selected the "Duplicate title tags" report. I then clicked on the plus sign on one of those results, specifically a conference coverage session that we covered at least three times under the same title. Here it is:
So, they all show different URLs, i.e. /archives/000161.html, /archives/001078.html and /archives/013900.html, but when you click on any of them, they all go to the /archives/000161.html version. So, I took a peak behind the HTML in webmaster tools to see, yes, Google is indeed linking every page to the first URL.
- <a href='http://www.seroundtable.com/archives/000161.html' target='_blank'>/archives/000161.html</a>
- <a href='http://www.seroundtable.com/archives/000161.html' target='_blank'>/archives/001078.html</a>
- <a href='http://www.seroundtable.com/archives/000161.html' target='_blank'>/archives/013900.html</a>
But why? Is this a bug or does Google really take the liberty to redirect them as duplicate pages to the first page? No!
A search for Search Term Research & Targeting returns two results at the top from the Search Engine Roundtable. Here is a screen capture:
Notice, the /archives/000161.html version isn't even listed in this version. If I expand the results, to show all results from the Search Engine Roundtable, then it will show a total of four results (not three) and it will include the /archives/000161.html result.
So, it seems like a reporting issue in Google Webmaster Tools and I would not worry that your site has major issues.
Forum discussion at WebmasterWorld.