Simple:
Any compliments or thank you's you might have, weather it is someone within the FG or you just want to tell people about family/friends etc...that has done something nice for you/someone else, it goes here.
It can be serious or just humor, you get the idea.
I thank my 2 1/2 year old son, for going into the kitchen this morning and feeding the dog :-4(i didn't even ask him to do it...in fact, i've never asked him to do it before)
And i would like to thank Minks for signing up to be my body gaurd