BTW, you just forgot to mention OpenOffice, Python Programming lang, Go Programming Lang, Dovecot IMAP Server, Vim and Xen Virtualization which are some majors open sources projects I know are using mercurial.

For the people who prefer Mercurial over git, do not worry, InDefero supports both of them and even Subversion (nice to share documents with Windows users).

I’ve used both Mercurial and Git to manage about 100 KSLOC worth of code on about 10 projects. I usually end up as the version control lead on projects, so I get to know these tools pretty well.

I’ve used Mercurial for over a year. It’s a solid, well-designed, beautifully-documented and very friendly program.

I’ve used Git for half a year. I regularly find it infuriating, confusing, poorly-documented, inconsistent, and until recently, also frequently broken.

However, I’ve chosen to do almost all my work in Git these last months because:

1. Git’s history rewriting features are fantastic — especially the interactive rebase — and are very useful for producing clear, succinct commits. Mercurial’s rebase is poorly done and mostly useless.

2. Git’s named branches work the way I want. Mercurial’s named branches is poorly done and mostly useless, e.g., you can’t delete or rename branches, so you’re constantly having to spawn new directories for doing feature-per-branch development to get around these limitations on named branches, which is obnoxious. The Mercurial 1.1 “bookmarks” feature helps somewhat but isn’t in the same league.

3. Git’s bidirectional SVN support works like it’s supposed to. This is vital for the many projects I collaborate on that have stuck with Subversion. Mercurial’s SVN support is import-only, which means there’s no way to commit a series of changesets back.

Just by themselves, these three features make all of Git’s annoyances worth it.