Rated 5 out of 5 stars

Used to use Websitewatcher for quite awhile but was never satisfied with the inbuilt browser. So I decided to look for, specifically, a browser addon that could do the same thing.

I chose SiteDelta and I must say I'm impressed so far. It does everything I want it to.
* Check only regions of a page.
* Ignore numbers.
* Highlight changes.
And, what I consider a bonus, it can also check changes to images.

One feature that I didn't expect but love is how it can detect when you visit a monitored page manually and it shows you the changes.

The one real draw back is the lack of a permanent visual alert. If you miss the temporary popup the only way to know is there are changes is to open the sidebar. Unfortunately, I find myself reverting to just refreshing the page, which pretty much defeats the purpose of this addon.

Please add an option for permanent alerts until clicked (or page is visited).

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

You are right, in 0.13.1 the visual cue that changed pages exist is not really obvious (it's the downward arrow next to the SiteDelta triangle).
The latest beta version from http://sitedelta.schierla.de/ provides a more obvious toolbar icon telling that changed pages exist.