What is "helpful reply" ???

The opposite of this. 

Venus
I was looking for a bit more detail. I'm guessing the owner of the thread would check it and not just anyone? 

In theory.
 

Venus
I mean there's "helpful replies" on tons of threads so it seems redundant and not really noteworthy as it was probably meant to be.

 
That pretty much describes the whole Coffee House! LOL. 

The noble idea of the "helpful reply" tag is to save readers time by skipping over the chaff and going straight to the best answers.
 
Being entirely user-defined, anyone can judge for themselves whether or not a post was helpful and pronounce their judgement, justified or not. Such democracy naturally dilutes the feature's value, but that is the nature of the internet. 
 
Of course, here in the CH nothing is to be taken seriously, so the tags have no real meaning. They are, however, a way to annoy fellow CH denizens, who'll receive an email notification every time you mark one of their replies as "helpful".

bitflipper
The noble idea of the "helpful reply" tag is to save readers time by skipping over the chaff and going straight to the best answers.
 
Being entirely user-defined, anyone can judge for themselves whether or not a post was helpful and pronounce their judgement, justified or not. Such democracy naturally dilutes the feature's value, but that is the nature of the internet. 
 
Of course, here in the CH nothing is to be taken seriously, so the tags have no real meaning. They are, however, a way to annoy fellow CH denizens, who'll receive an email notification every time you mark one of their replies as "helpful".

For some odd reason, when I initially set up my Cake Forum account, I used an alternate email address and not my primary. Not that I'm getting flooded with "Helpful Posts", but it certainly has worked out well.