Windows – Does iTunes 11 need extra services or tools to manage duplicates in the library

In the new version of iTunes 11 the find duplicates option is gone and I don't want to revert to iTunes 10 to get that function back.

I know I had 1 GB of duplicates in iTunes 10, but I can't have iTunes show them to me anymore. My first thought was wondering if iTunes 11 finds/delete/merge them automagically?

I mean, I know that I had two versions of "Lemon Tree", one is the original one and the other is a cover, but now I can't find the cover anymore. The same with other covers.

I ran http://www.macroplant.com/meta-tunes/, and I only found 3 duplicates, while I am sure I had 100+ duplicates, because last sunday I imported a lot of songs and the "find duplicates" found 800 MB.

If anyone has insight into what iTunes 11 does when upgrading a library that would be a great start, but I'd prefer an ongoing plan to keep my library minimally duplicated.