Comments on YouTube videos are often anything but enlightening, so it's good news that you can now opt out of viewing them altogether.
Just select 'Options' next to Text comments and tick the option to Hide Comments. There's also an option to filter "coarse language and racial slurs", according to Google Operating System, but that doesn't seem to appear on every video. For a more sophisticated approach to managing YouTube comments, check out the previously mentioned Comment Snob extension.
[via Google Operating System]