Example:

I believe this would be a useful functionality to include in IPB 4.0 and even possibly hook for 3.4.

There are situations in which a member may want to follow a thread, but they only want to receive updates from the topic author and don't want to be spammed with "feedback posts" from other users.

Notifications need major improvements , they need to work globally on a similar method.

I also liked your idea , it should also allow us to group only thread responses , similar to how facebook works. If a thread receive more then 2-3 respond , all those should be highlighted within one single row