The main problem that people have with PhysX seems to be the huge driver. Just for information - I can guarantee that you won't need the driver when physics is not used in your app.
It is very likely that in the future the PhysX driver is automatically installed, or at least available when you install an nVidia card, and will probably become just as easily available as the DirectX library.
What we certainly won't do is implementing different libraries in the Commercial and the Pro Edition. We will support only one library, and will maintain backwards compatibility to the current physics functions.
