No SDL or SFML?
http://www.libsdl.org/ http://www.sfml-dev.org/ They're two wonderful multimedia layers that work excellently with OpenGL-based code.
Also, I think that it's a bit unnecessary to include Assembly in the list of programming languages; at the least, it shouldn't be at the top of the list. Its use is definitely necessary on simple platforms where handwritten Assembly greatly outperforms anything that a C compiler could ever produce; it's also helpful for speed-critical operations and the rare times you'll need extreme control over hardware (though on most modern x86-based machines this isn't usually possible anyways.) However, 99.999% of the time when you're writing a game in C[++], a modern compiler will generally produce much better machine-level code than someone could hand-write. Even on devices such as smartphones that have an OS that don't often allow decent use of peripherals like FPUs (especially with older Android-based phones), dipping into native code gives a bit of overhead (like with JNI) that makes random integration of native code a bit useless. Not only does putting it at the top make it seem like it's an everyday-essential in the Game Dev world, it also may make people who click it first look at all of this with a "OHHELLNO" reaction, since I think it's agreeable that Assembly is not a comfortable first-dive into the world of Computer Science and programming

I like the addition of Trello into the list of management tools; I've used it a lot for various projects and it's been extremely helpful for keeping ideas in check. Notepad++ is also another good list item; as for something to add, Netbeans (
http://netbeans.org/ ) is what I use for larger projects as an IDE.
Since people may want to take on the task of creating some music for their games, perhaps add a list of some programs that make it possible? If you choose to, I'd put a disclaimer explaining that creating music is like creating visual art and both take a lot of practice and learning. As for what you could put on the list,
https://www.ableton.com/ http://lmms.sourceforge.net/ http://famitracker.com/ http://openmpt.org/ http://www.image-line.com/documents/flstudio.html are some things you could put for starters.
It was a great idea to make this topic, for those who don't know anything about game development and want to learn all of the aspects needed!

EDIT:
Searched around for some more material to be added.
OpenAL --
http://connect.creativelabs.com/openal/default.aspxLWJGL --
http://www.lwjgl.org/ (Basically a wrapper to OpenGL/AL/CL for Java)
Panda3D --
http://www.panda3d.org/ (Haven't used but heard good things)