AllinOne SEO Pack – use this plugins to quickly insert the Meta description tag and Meta keyword tag into your post. Also, you can use it to set a search compliant URL scheme, and eliminate duplicate content by adding “no index” tags where applicable. You can download it from http://wordpress.org/extend/plugins/all-in-one-seo-pack/#post-753.
Google Sitemaps Plugin – install this plugin to automatically generate XML sitemaps and ping Google when a new page is added to your blog. This is a must-have for any blog. You can download it at http://wordpress.org/extend/plugins/google-sitemap-generator/#post-766.
Google Analytics for WordPress – will help you to easily connect your blog to your Google Analytics account. I would recommend treating your blog as another website as far as Google Analytics goes. Downloadable from http://wordpress.org/extend/plugins/google-analytics-for-wordpress/#post-2316.
ShareThis – use this plugin so that visitors to your blog can send your articles to a friend or submit them to the social web. Downloadable from http://sharethis.com/.
Don’t forget to register with Feedburner, so you can grab metrics about your RSS subscribers.
I would also strongly recommend registering your blog with blog aggregation sites, such as Technorati, to increase your web traffic and inbound links to your blog. Generally, the more you participate in Web 2.0 communities the more traffic you’ll drive to your site.