When binding to KeyUp, events only fire if a form input has focus
That prevents various scenarios, like keyboard navigation of a list / grid, and also things like keyboard shortcuts.
Fiddle to demo this is:
http://jsfiddle.net/JXwWC/
I can understand there may be performance reasons for this, and couldnt see the code that caused this, but be great if this can change (and happy to submit a PR if someone points out where the choice to only bind if focussed is happening