I wanted to mention a few WordPress plugins I've been using for blogging for niches and for creating supporting blogs.

Platinum SEO Pack - This plugin, which is a branch off of the All-in-One SEO code, provides robust SEO functions for WordPress blogs. Platinum SEO takes it a step further by offering nofollow, noindex and redirect functions.

Insights - This admin area AJAX plugin allows you to search for material related to your supplied keywords on YouTube, Google,...