The new Joomla! 3.2 feature is MUCH better. Since I was writing a core Joomla! feature I was allowed to modify core code (something I couldn't do when writing Admin Tools). For starters, each user can have his/her own Google Authenticator code. In other words, if you have ten Super Users each one has a different secret code, making the implementation much safer. Then you can select if this feature will be available only to the back-end, only to the front-end or both in the front- and back-end. I recommend the latter: both front- and back-end. It's more secure.
In addition to Google Authenticator I also added support for YubiKey two factor authentication in Joomla! 3.2. If you've never heard of it it is an inexpensive (~20 US Dollars) hardware token that plugs in a USB port. The idea is: go to your site, enter your username and password, click on the Secret Code field, plug in the YubiKey to a USB port in your computer and touch its button. The YubiKey produces a secret code which is then validated both on your site and through a third party service. This is even more secure and easier to use than Google Authenticator.
On top of that Joomla! 3.2 has a much better password encryption algorithm (bCrypt instead of salted MD5) and a massively improved "Remember Me" functionality. All these featured combined offer an excellent upgrade in your site's security.
Nicholas K. Dionysopoulos
Lead Developer and Director
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