Remember in your settings you can set it so you get a notification in your PM box if someone quotes a post. I use it so i dont have to go through each thread and see if i was quoted. Its hilarious how terrible the VB notification system is. Xenforo really has it down. Most of the free forums have great notification alert systems. I feel like we are in the stone age at times with VB.
Anyways if you want to use that feature.....
Settings>General Settings>Quote Notifications(Scroll down)