I think it is different between topics opened "just" to raise a discussion, and informative posts like answers to specific questions, or tutorials.
I think that Toadtorrent was referring to the second type of posts when he started this topic. And I thank him for doing it.
What I can say is that, when I answer a specific question, a reply -- even a simple "tank you" -- is appreciated.
A "thanks" rating is appreciated as well, but especially from members who are not the one originally asking the question.
I also have to say there has been a time, a few months ago, when courtesy was looking almost forgotten, but now things are going much better.
On my personal book, anyway, those who don't even care to leave a thanks when I answer their question(s) are going to get no new answers from me on possible next questions...