Feedburner - WordPress.com provides users with statistics about feed subscriptions. At best, these metrics were questionable and I used to provide two RSS feeds (WordPress and Feedburner) so the metrics didn’t capture all feed activity anyway. As there is no equivalent functionality in WordPress 2.0.4 out of the box, I resurrected my Feedburner account and installed this WordPress plugin which automatically routes any subscribers to the WordPress RSS feed through Feedburner.
Sitemap - I started from zero when I created this site so I could try my hand at organic gardening. The only search engine I submitted to was Google. When I was trying to encourage Google to index the new site, I discovered that a sitemap could accelerate the process. This WordPress plugin generates a sitemap which tells the Google crawler about the site structure and recently updated pages. The sitemap automatically gets updated after each post and helps to reduce network traffic.