Dave Lighthart recently produced a summary of the Top 1000 WordPress Authors and Plugins. The results are a bit confusing:

• Automattic appear in 2nd, 10th, 15th, 17th and more positions
• The figures show the accumulated downloads of ALL the plugins developed by each author.
• It also names the most popular plugin… but the link is to the plugin’s home page, rather than WordPress.org.
• So click on the user’s profile link instead