Oh, my:) You know, I appreciate your help for pointing and explaining me the down-votes. There is one thing I want to say though: If this Karma thing is important for you guys, just do what you think is best. As for me, I don't care if my Karma here is like -xxx or +xxx, alright? I registered here for more important purpose, like getting to know good people and read good news I missed in my Google Reader. I don't troll here, so if I feel like saying a thank you to one of you, I will do so. As I said before, do what you think is best. Cheers!;)

It's not about Karma and points, it's about the quality of the site as defined by the current users. You weren't downvoted for trolling, but for the style of your comment. LOLspeak and emoticons are standard elsewhere, but not here.

Generally, your 'thanks' will be better appreciated here if you use the best standard English that you know. You aren't being punished, rather your comment was being moved lower on the page to make room for better ones. You can choose to ignore the feedback this rearrangement provides, but your stay here may be more enjoyable if you pay some attention to the local customs.

I'm not certain, but I think that once a particular user's karma falls below a certain threshold, all of their future comments and submissions get auto-killed.

I think it's the general texture of the "LOL", smiley emoticon, and exclamation more than the gratitude. A comment that doesn't add much, and looks like it was made quickly often produces bad results here.

Maybe it's because people are scared of losing the fantastic signal:noise ratio that's a hallmark of Hacker News and is very hard to find in internet discussion. The parent comment looked like more general internet discussion, but if he'd written, "This is exactly what I needed to hear in plain English: I keep meaning to code up this simple timezone app but I've been scared to execute it. Wow, that was valuable" - well, that probably would've been quite high in the positives.