Why single out software patents for death? There is very little distinguishing software patents from any other patents.
I've heard the argument that mathematical equations cannot be patented and all software can be written in a mathematical form, therefor software should not be patentable. But that argument can also be applied to mechanical contraptions. As your friendly CAD package knows, any mechanical device can be expressed as a set of numbers - loosely a mathematical equation.
I've heard the argument that software is just comprised of layers of pre-existing ideas. So too are any mechanical contrivances held together by screw or manufactured using drills etc.
With more and more embedded systems it is getting really hard to distinguish where the software begins and the hardware ends. That makes it even harder to draw a line between the two. Should a mechanical musical box be patentable, but a full software simulation of the same idea not be?
Surely software IP is as worth protecting as hardware IP, or conversely both should go. I've yet to see any rational reason to say that software patents should go while mechanical ones should stay.