This extension allow you to count each page's talks and display this number next to the tab.
Firstly, the "FlowCounterTalks" extension depends of the skin "Chameleon", without it you can't use "FlowCounterTalks". And it needs also the "Flow" extension, download it and then download and extract the extension file inside your "extension" repository. The extension's repository must be called :"FlowCounterTalks".
Once you load the extension, at the end of your LocalSettings.php file add the following line :
wfLoadExtension('FlowCounterTalks');
And that's it, you should see the new counter next your tab title.