To be fair to the subversion guys, its pretty darn easy to setup real-time backups. Use svnsync and hook it up in some post-commit hook.
Having said that, to have git completely backed up, it's not as simple as a clone. You will need to mirror another repository so that you can get all of the branches, tags, etc. Additionally you will need some sort of post-receive hook so that your mirror is kept up-to-date.
Now, my conclusion with backups for svn and git - both need some intervention. Its not as simple as "press this button and it just works".
git wins fast over svn for backups.
git backups are redundant, always up-to-date, easily verifiable, and easy to turn into proper master repositories.
The more people you have working on a project, the harder it gets for anything to get lost.