Free theme that deals with this...

[swimby]

http://www.seomoz.org/webinars/advanced-wordpress-seo

this video highlights some duplication problems in some of the free themes - does anyone know of a theme that deals with this?

[BenRWoodard]

I use Standard Theme for all my blog sites. It integrates the core functions of WordPress SEO by Yoast with a really well coded theme.  As far as the duplicate content.  Wordpress SEO by Yoast lets you deal with what items to nofollow and noindex very easily on almost any theme.

[TakeshiYoung]

A good alternative plugin is All-In-One-SEO. That should take care of most the SEO issues with Wordpress.