WordPress is by far the most popular CMS used for websites today...it powers nearly 73 million. Like Joomla it is also open source with a great user base constantly expanding it's functionality. Primarily developed as a blogger interface with the addition of plugins WordPress now has the ability to achieve most anything desired in personal to small business web presence. Though no longer pronounced compared to Joomla WordPress has focused on SEO at it's core and as well has multiple plugins developed specifically for e-commerce. It is a very extensible and expandable CMS that once turned over to you is easy to update. For those that are familiar with the administrator interface of WordPress over Joomla this may be the best option.