Not for everyone but this is a very useful tool for anyone wishing to capture good quality screen images and then make notations to be shared.
I extensively use a browser add on called FIRESHOT which is available as either a free or licensed product. The free version is all most of you need and has all the functionality to make this a useful tool for whatever browser you have.
I find it useful as a communication tool because I can take a shot of a whole or part web page and mark changes on problems and then send the image with notations to clients and developers.
This is by far a more effective communication tool than trying to explain visual changes in writing.
All images are good quality and there are certain edit functions included.
For more information visit http://screenshot-program.com/fireshot/ from where you will be able to find the download version for your particular browser.