"Thank You" system just has been installed at forum.
From now each post has button THANKS at left side under poster "profile". Also forum will inform you if one of your post got "Thanks" via notification system (as it informs when you have new private message). If such notification annoying you - you can switch it OFF in your account : SETTINGS (top-right corner) - GENERAL SETTINGS (left column, middle) - scroll down till the end of section Messaging & Notification and uncheck box near last point "Notification for new "Thanks" on your posts?"