We’ve recently started working heavily with WordPress. What became quickly apparent was that there are some must-have features (for us at least) that don’t come with a vanilla WordPress installation.
WordPress SEO by Yoast
I was surprised to discover that WordPress has no built-in support for basic SEO related tasks such as customising the meta title or adding meta descriptions to posts or pages. The web today is driven almost entirely by search, which makes this omission all the more glaring.
The WordPress SEO by Yoast adds support for many SEO-related tasks, including the basic meta tag editing on a per-page or post basis, adding site-wide social metadata and connecting your site to external search tools such as Google Webmaster Tools.
WordPress SEO goes further, adding advanced features like focus keyword analysis, breadcrumbs & XML sitemaps just to name a few.
All in all, a fantastic plugin.