Plugin: WordPress Duplicate Content Cure
Update: 3-04-07
You can change line 24 in the plugin from:
if((is_single() || is_page() || is_home()) && (!is_paged())){
to
if((is_single() || is_category() || is_page() || is_home()) && (!is_paged())){
and that will put your category pages in Google. This plugin is very simple and can be modified very easily.
I just installed the WordPress Duplicate Content Cure. WordPress creates lots of different pages that are very similar or completely the same. What it does is put a “noindex,follow” tag on these pages.
Be carefull with this plugin it can hurt your rankings. It is very common for a blog to rank for category pages. This plugin will remove all pages other than the ones you create. It will remove the category pages from google. Category pages rank well in Google because you end up with a pretty high keyword density and the internal linking. I am not recommending this plugin just testing it out. I may end up making some changes to it. I think it is a good idea just knocks out a bit too much.

