If you're looking to use it for anything other than unmodified internal use, be aware that it uses the AGPL license (the "A" at the start being quite important), and may place restrictions on what you want to do, much more-so than the GPL.
I think that AGPL requires you to give source code to the users of the program. If you use a modified version internally then you'll have to give the source code to your employees. That isn't as problematic as sharing with the whole outside world.
