For Google tags links are common links nothing more. There are no meta informations for tags. And sadly nobody has control on Google SERP.
I'm sorry i've to say what i'm going to say but i've to do.
Don't take Joomla too seriously for SEO. Because Joomla has a lot of errors, problems and it's an old story that Joomla is not good at SEO. Take for example the pagination links, they are fully bugged also in J3.3, using pagination non-SEF parameter for canonical links. Unacceptable error.
Now 2 examples.
1) You install Joomla 3, cool! Joomla 3 has tags, so let's go to enable tags so all users will be able to search contents using tags. Cool! All users that visits your site like tags a lot! And every user makes 10 clicks per visit on tags links and only 2 on links in the main menu. Now question: what do you that will be the links that Google will show firstly in SERP? Well... sadly of course tags links.
2) To make things even worse, look at source code for tags links pages in your site:
Code: |
http://www.techvalue.net/index.php/en/component/tags/tag/182-google-camera
http://www.techvalue.net/index.php/component/tags/tag/3-zopo-gr
http://www.techvalue.net/index.php/component/tags/tag/2-zopo-zp700-gr
|
First of all they are not fully SEF and look ugly having 'component/tags', but even worse.... they have all the same title! That indeed is not a title but only the site name:
Code: |
<title>TechValue.net</title>
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This means that Google is free to show an arbitrary title in SERP for these links.
Results: tags links are the most important links in my site and all have the same titles... very very bad.
Now sitemaps. Sitemaps are meant to submit a bunch of links to Google and say: 'Hey These are links in my site , place them into your index and use it as you think it's better when users make searches'. Sitemaps can do quite nothing to manipulate SERP, as i said the only factor is the priority variable that helps Google to understand the most important links in your site. Of course Google is free to don't believe that, if you have 100 clicks on tags and 10 on main menu.
Finally, look at this site....left menu, 'CATEGORIES'. Well i'm bit liar. That's not a menu. These are tags, Have you ever thought that were tags? Now try to open the links and look at source code and titles. All the tags have a well formed page with custom descriptive titles. Of course this site is built on a fork of Joomla with a lot of errors corrected. SEO is an ugly beast!