Hi Duarte, also here are some scripts that will let you jump to a particular maximized viewport with one keystroke:
http://moi3d.com/forum/index.php?webtag=MOI&msg=3808.2

Although it is possible to manipulate the 3D viewport to different positions like Top, Right, etc..., it won't be quite 100% the same for drawing things, when you draw things in an ortho view there are various additional 2D drawing aids that will kick in, like you'll get the edit frame for quick scaling and rotation, and once you start drawing something like a curve in the 2D view it will remain planar to that view with things like snap points projected to a plane going through the first point you picked.

Basically there is some additional functionality to help with drawing 2D things when you are in one of the 2D viewports, those things will not be activated if you are still actually in the 3D viewport just with its view happening to be aligned with an ortho view direction.

Just something to be aware of...

- Michael

Oh right, I wasn't aware of that Michael, thanks for the warning, I'll keep that in mind!

For quickly checking the model these are still useful as the can be reversed back to a 3D view simply by orbiting.
That post is very nice, it also answered my questions about setting Numpad keyboard shortcuts!