Indeed, publicity was the plan. Barr hoped his research would "start a verbal braul between us and keep it going because that will bring more media and more attention to a very important topic."…But within a day, Anonymous had managed to infiltrate HBGary Federal's website and take it down, replacing it with a pro-Anonymous message ("now the Anonymous hand is bitch-slapping you in the face.") Anonymous got into HBGary Federal's e-mail server, for which Barr was the admin, and compromised it, extracting over 40,000 e-mails and putting them up on The Pirate Bay, all after watching his communications for 30 hours, undetected. In an after-action IRC chat, Anonymous members bragged about how they had gone even further, deleting 1TB of HBGary backup data.
These answers are of course all correct to an extent, but do not account for WordPress' success by themselves. Not by a long shot. The truth is that WordPress won for a whole host of reasons, including the act that WordPress has more themes, more plugins or a larger community. These too are important considerations, but these are by-products of its success, not the reasons for its success.
So let's break it down shall we? Let's talk about the commonly cited reasons for WordPress' success, and some less well known reasons as well.