They both are about the same but Thanking the writer is what really shows on your profile. If you vote with the green button then you should by rights Thank the writer also. Since you're new, you may want to check out this video that Kass made that sums up how to use the site. Welcome to blurtit! Plus the more votes an answer gets the further up it moves in popularity.
www.youtube.com/watch?v=rn5YOWyeQaE
