some hard (though not necessarily relevant) numbers

Now, if there weren't any other similar software, that needn't matter. A lot more Word documents get created every day than git commits, but that's no reason for programmers to consider choosing Word over git. But the reality is that Bazaar isn't so different from other DVCSs, and while the difference between CIA's statistics for CVS or Subversion and say, Mercurial, might be accounted for by some small variation in usage style, the huge gap between Bazaar and almost any of the others can't be explained that way.

If there are ten (or as seems more likely from those stats, several hundred) times more git users than Bazaar users then on average Bazaar users must be a LOT more proactive in supporting Bazaar to have the same impact. That's just not likely to happen.