If you see a post you rather like, find usefull or helpfull in any way you can click on the button and it add’s a thank you post below the post with the names of the people who have thanked you… see below your post
The thank_you add-in is a way of letting people know that the post was helpfull. A public reputation system if you like, although it has no impact on the reputation (although it can).
I added this earlier today as I had seen it in use elsewhere to a positive effect alongside reputation. It was one of the things that came up whilst reading many threads on the impact of negative reputation on other vbulletin forums. It has also been used on some forums to stop those who are still intent on raising post counts posting continuous “thanks” threads with no real comment to them.
As you can see, the option to turn off is there if not used or not wanted, but there has been a widespread use this morning, although this may have been simply because it is something new.
The add to reputation part of the “thank_you” has not been enabled. This value is fixed in this mod, it does not plugin to the reputation “power” that is part of teh reputation feature, and hence in my opinion best to keep the two things seperate but mutually agreeable.