I can see it's useful to be able to control how far you zoom out by drawing the box.
However when you click, nothing happens. This is counter to every other zoom out tool out there and users will be surprised by this. Drawing a box for zoom out is not intuitive.
Why can't it be done so a click zooms out by a pre-set amount, yet drawing a box allows the user to control how far you zoom out? Then you have the best of both.
Personally I don't like the zoomin-by-point / zoom-out-by-point navigation. Dragging a rectangle is faster and convenient to the usage in desktop applications.
Do you know if anyone's actually implemented a single click to zoom out handler? Would be great to add this in.
It's not a matter of personal favourites, its user expectations. I haven't seen any other software package where a single click in "Zoom Out" mode does nothing. The users will expect it to do something.