Something to put on your list of site improvements - the text of the message:
The Following User Says Thank You to abcdefg For This Useful Post:
could sensibly be revised to read:
The following user says thankyou to abcdefg for this useful post:
This happens to be correct English, but the reason I suggest it is that, where the user being thanked has a lower-case username (as many do) his name is effectively smaller than the text surrounding it and gets lost. Also, it would look that tiny bit neater and less cluttered. I recommend placing this change in position no #123,327 on your to-do list.