Category Content Duplication

[SEODinosaur]

Does indexing category archive page for a blog cause duplications?

http://www.seomoz.org/blog/setup-wordpress-for-seo-success

After reading this article I am unsure.

[AlanBleiweiss]

Categories are your primary keyword topics - the primary topical focus grouping of your blog.  They should be the umbrellas that contain underneath them, any articles closely related to those highest level topics.

Think of blog categories as the equivalent of main services pages or main product categories in an eCommerce catalog.

In order to build authority and trust for a category topic, you need to build depth of content over time under each umbrella.  Indexing category archives is the best method for having search engines recognize that depth of content.

As such, it's vital to allow these to be indexed.  Simultaneously, it's unwise to allow indexing of date based archives because those are going to create potential duplicate content conflicts, either partial or entire duplicate representations.