wordpress排名遥遥领先于drupal,joomla --来自 http://w3techs.com/

Usage of content management systems for websites

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This diagram shows the percentages of websites using various content management systems. See technologies overview for explanations on the methodologies used in the surveys. Our reports are updated daily.

How to read the diagram:
61.9% of the websites use none of the content management systems that we monitor.
WordPress is used by 23.3% of all the websites, that is a content management system market share of 61.0%.

http://w3techs.com/technologies/overview/content_management/all

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这篇文章写的也不错：

http://www.smashingmagazine.com/2011/11/29/wordpress-cms-crown-drupal-joomla/  

不管是排名前三，还是top20的cms，都是不错的。
具体还要看个人偏好。
至少从中小企业网站市场竞争力来看，wordpress优势是很明显的。