I agree -I think there are two different issues being discussed on this thread.
1) whether a like button would be nice to feed back appreciation to an author.
2) whether pressing like should change the post order so popular threads are prioritised.
Personally, I quite like the first as if you're new to the hobby some of the more polarised discussions can be difficult to follow. Sometimes wrong people can be more noisy than right people :banghead:
I've seen on other forums that a "like" count helps with differentiating good information from bad, without stifling the discussion. E.g. person A says it's left hand thread, person B says it's right hand, take a look at the likes and you can see who most people agree with.
That's good feedback that doesn't end up in an argument, though luckily we're a more reasonable crowd on here than on many internet forums and don't suffer from too many heated discussions.