Subversion's initial release in October 2000 was important. It established the concept of atomic commits that captured the entire folder rather than the "file-by-file" approach of its predecessors.
Git extends that model with full symmetry between the server and client. Non-linear history allows a variety of workflows that were impossible with SVN. Once you've tried it, you won't want to go back.
You don't have to switch everything to git at once. Using git-svn, you can checkout from and commit to an SVN server using git.
Once you have setup your local copy at the command line, you can use DiffPlug's git client with your SVN server.