Being told of a new post when you reply to a Thread
 

I noticed of a few SMFs that when a user replies to a Thread but during the time that user has wrote his/her post another user has replied to the same Thread, it automatically tells you this before submitting your post.

Is that feature available for vB forums?
Or is there a mod available for this?

There was a mod for this, but I don't think it ever got out of beta stage. I just installed Live Topic instead which works fine for me. (Some people have problems with that mod.)

What does that mod actually do?
I read the info for the mod but I am not really clear.
How would that help with knowing that just as you posted another post above it has been made?

Basically, if a topic is 'live', then the posts just show up on the page without you refreshing. The developer has a youtube video linked in the first post.

Some people have problems with it, so it isn't for everyone. You can search for that other mod, but like I said, I don't think it ever got out of beta stage. (Although, I suppose there could be a new one I just don't know about.)

Thanks Lynne, I have installed it but it doesn't work, I am waiting for support on the Thread.

It won't work if you have certain other mods installed (they are listed throughout the thread) and some people have server configurations where it just doesn't work either. I know I had to change some of my mod_security settings to get it to work.