One VCS to rule them all... Having gone through different VCSs of varying (mostly poor) quality and cost over the span of my career, I am glad to see that that a de facto standard seems to be being settled on. Git is quite good, far better than any other solution I have used on a day-to-day basis. (No disrespect intended to Mercurial, etc.) While having a breadth of technological solutions to problems is frequently a…
While I'm all for abandoning old and often awful VCSs, I do think there's room for some diversity. Git's not really my thing, and I'm happy to be able to use an alternative. Most DVCSs work in very similar ways, and for standard use, I don't think there is a huge learning curve for someone switching between git and mercurial, for instance. Some other tools have their own benefits, like fossil with its nice integrated…
And in that sense, there are really high costs to variety. Imagine a world where you need to be fluent not just in whichever two of RCS/CVS/subversion/git are currently en vogue, but also mercurial, SCCS, bitkeeper, Perforce, ClearCase, etc... That's a mess.
So sure, git might not be "your thing", but I strongly suspect you'd still prefer a git-only world to one where every project you want to tinker with uses a different SCM.