It's interesting how most comments on this thread have no issue with the fork, yet most of the comments on the blog post are very much against the fork. (Strange considering they are mostly from the WordPress community).
From the languages & compilers to the frameworks & API's, every day we stand on the shoulders of giants who made it all possible (written on a machine running a commercialised fork of BSD).
After all, is it Open Source, or Free Software ;)
(written on a machine running Windows, sat next to a machine running Ubuntu)