A recent teardown of the iPod touch by research firm iSuppli suggests that the total cost of components for the 8GB model is $147, or around half of the device?s $299 retail price. iSuppli?s Andrew Rassweiler believes that the iPod touch will likely serve as a blueprint for future iPods, saying, ?We expect the click-wheel versions of the iPod to wane in favor of touch-screen-based models.? Inside the 8GB iPod touch, iSuppli?