A+++ Rated 5 out of 5 stars

Thought I had already written a review but ... anyway, have been using since I started using Firefox though I believe I was using "Adblock", not Adblock Plus. This add-on is the best! Increases browsing speed by blocking intrusive ads and protects against tracking. If you find that a trusted site is not loading properly, just disable with a click. I love how it works on Facebook!

This review is for a previous version of the add-on (2.3.2). 

Rated 5 out of 5 stars

I have had this installed since I discovered Firefox about a year ago. So seamless you aren't even aware it is blocking most of the time.Try it on Facebook first with and then without Adblock and you'll see what I mean.
As a side note-To be honest, I am not well versed in "computerese" so I don't mess with the filters. If I find that a website I trust is being slowed, I disable.
For those who DO understand file types, scripts, etc, it is hugely customizable.

This review is for a previous version of the add-on (2.2.4).