Brent Sordyl's blog

Subversion is still the big gorilla in the room. 47% of developers use it as their primary version control system at work. But, distributed version control systems (DVCSes) are coming on fast! Git and Mercurial have each stolen 14% of developer allegiances. And, CVS, Perforce, and Visual SourceSafe, once dominant, are now on the run.
For one, Windows 7 has already become the leading development platform, with 31% of programmers using it as their primary platform for coding. 70% of programmers today are Windows based, 16% use Ubuntu/CentOS or other Linux, and 14% use Mac O

(Full Story: The State of Version Control – FogBugz Blog)