Just a bit of clarity. The Thankyou button is about the size of the reply button at the bottom of your post. A person isn't automatically notified when someone clicks the thankyou button at the bottom of someone's post. As far as clutter goes compare the amount of sig lines you have to the size of the reply button. I am also on another forum that has it and my own experience is its a good thing, allowing people to show a bit of appreciation if they don't have allot to say. I don't find that it visually gets in the way at all.