If you want to tag based on article words or metadata - which is the way to go - and want something fully integrated with Joomla/search/SEF/ even forums like Kunena and PHPBB3 then this is the way to go, without question. Perfect tagging addon and very well done I might add.

First, it does exactly what it says it does - adds some much needed validation to your standard registration page. Then it goes beyond that with little touches, like Ajax checks against whether a username is already in use, password strength meter, and best of all BotScout support.

You'll need a (free) ReCaptcha keyset but that takes roughly 30 seconds to get. You'll also need a (free) Botscout API key but that takes even less time. Between those two spammers are going to have a hard time of it registering on your site. BotScout alone cuts most of them out.

I could do with a little more customization, the admin config is very bare-bones (missing css, looks like) and the Welcome/Intro header up top is too wide for a lot of sites, but those are minor tweaks that don't detract from the good work that went in to this.