 <p>Canonical (Ubuntu) tracks <a href="http://popcon.ubuntu.com/by_vote" rel="nofollow">software package usage</a> for their distro, so there's no need to rely on Stack Exchange issue counts to measure popularity. However, as others have pointed out, this only tracks Ubuntu users and Canonical (Ubuntu) uses and recommends bzr (sample bias). Nonetheless...</p> <pre><code> 2011 2011 2011 Package Aug 3 Sep 29 Dec 9 Change ------ ------ ------ ------ ------ git-core 3647 3402 3236 -11% bzr 4975 5286 6070 +22% mercurial 3411 3387 3461 +1% </code></pre> <p>The decline in votes for the git-core package makes me think I've done something wrong like <code>grep</code>ed the wrong package name from the ubuntu popularity table. Or maybe even this "vote" count is related to installations and not actual usage of the software.</p> <p>Here's some historical data for trending. I used the <code>&lt;install&gt;</code> rather than <code>&lt;vote&gt;</code> stats from Ubuntu in this table, but it shows a growth spurt in Bazaar and Mercurial starting in 2011. Nonetheless, <code>bzr</code> was behind <code>git</code> in 2011, but the recent stats for 2011 show that it passed <code>git</code> in total installed instances (on Ubuntu).</p> <pre><code> June Aug Dec Growth Oct Growth 2010 2011 2011 2013 ---- ----- ---- ---- ------ ---- ------ git 94k 159k 171k 80% 165k -3.5% bzr 52k 121k 135k 160% 170k 26.0% hg 36k 68k 75k 110% 95k 26.7% </code></pre> <p>Discalaimer: I used bzr on Ubuntu until 2012 when I worked on teams that used <code>git</code> exclusively. <code>Bzr</code> plays nice with all other VCSes, allowing you to use consistent, intuitive bzr command line syntax. My switch to <code>git</code> was for social rather than technical reasons.</p>