Keyboard is at least 100x as productive as mouse (assuming you know what to do and what to type). Even the best peachy UIs cannot change it. Still there are things that aren't convenient to do from CLI like photo retouching, but these are quite obvious exceptions.
That said, I'm not sure what would you like to do in such terminal?
My question was in fact about features that this command bar does not provide. Part of the ones you mentioned was already available before (like file editing), but simply not in a CLI-related manner. Some of these they could surely add, i.e. whatever can be put in this command bar yet not turning it into terminal.
If you're going to do real job, just do in your real terminal emulator, xterm, rxvt, you name it. What's the point of having GitHub terminal in browser? If you want to do quick'n'dirty fixes/improvements directly from the browser, then it's like asking yourself for troubles, because there is quite higher chance that you'll commit a mistake (even literally speaking) than if you'd be using your own terminal that you work with on a daily basis.
I agree that a keyboard is orders of magnitude more conducive to productivity, but I'm surprised that you do some of these frequently enough to make learning the commands a worthwhile endeavor, if one of these consoles were available. Even starring/unstarring is something that I do frequently, but I don't think I'd get any boost out of typing 'star' instead of just clicking on the star when my brain is already saying "make that star thing light up."
My point of view is based on personal experience. I explain it:
Git was initially a set of commands from terminal. A lot of programmers use terminal everyday. Even now I have terminal opened for doing different stuff. This terminal-nature of git itself and of github audience makes it obvious it would be used.
The other interesting question is how it would be implemented. With my repos on github (as opened as private) I think it would be great to have an opportunity to do some set of things from the site CLI.
P.S. I understand there are a lot of those who prefer GUI over CLI but I believe I am not the only one who wants to have CLI also available.
