A couple of improvements.

Enabled AA, everything looks smoother.
Whenever you zoom, it zooms on the mouse.
When zoom is < 1, and the selected planet is in view, it locks it to the planet.
Period (or full stop key) will now centre the camera on the selected camera.
Fixed the title. :P
Added mouse position to debug menu.
Well, this one you kind of brought upon yourself.  
I mean, if you've put each term on a newline to make it better to read, the least you could do is align them.