WordPress 3.3 has been out for several weeks now and we have not heard of any issues or problems with it. This release mainly streamlines the backend and makes site administration even faster and easier than before.
We recommend making the update to 3.3 now. As usual, we recommend creating a backup of your site and your database, before the update. While we don’t expect any issues with the update, it’s always good to have a spare backup.
