what is there to discuss anyway? The name grew out of the original iPod line and there's no reason for them to change it. the iPod Touch came before the iPad. and the touch is basically just an iPod anyway.
Carl Sagan once said, 'extraordinary claims, require extraordinary proof'. With this concept in mind I might say that a decent discussion requires a decent topic, and however you want to slice it, I'm afraid that musing over why and iPod with a touch screen is called and iPod Touch, is not going to do it.
That's kinda like asking why Apple doesn't rename the iPhone to "iPad phone".
The above post is correct.
The Touch is not a tablet by dint of its only having a 4" screen. The lines are becoming blurred, though, and the Touch has the same innards as the iPad Mini - just with a far better screen.