Wordpress is by far the most commonly used content management framework for web development. We have designed numerous websites using wordpress as the backbone over the years. Many folks have used the system before and wish to continue.
There are a plethora of plugins available to accomplish a wide variety of tasks, such as SEO meta description and title entry, CSS minification, and browser caching. (to name but a few). Wordpress, while easy for most site administrators to use, often poses security issues- frequently by mySQL injection attacks on outdated plugins. The key is to monitor your site frequently, and update those plugins when needed.