Git - because I was doing useful things with git in a day and never really could get my head around SVN and make the transition from CVS to SVN.
If you know SVN it might be different or if you really like the more hierarchical model of CVS/SVN, but I can't think of why anyone would.
Also, git effectively acts as a backup because every repository includes all data (unless you do a "bare" repository, which you might for a central repository).
To me, SVN is outdated. Git has also been surpassed by systems that take the git concepts and refine them, but git has so much documentation out there - videos, free e-books. As a handy reference, I bought Scott Chacon's "Pro Git" from Apress and I thought it was worth it ot have next to me when starting and when I get out of the habit and am using git again after a pause.