Its a valid question, cooler CPUs should mean we could a apply some reasonable volts yet still maintain very quiet systems with some of these awesome CPU coolers that have come around thanks to a past trend of CPUs getting hotter and hotter.
If these early performance numbers are true, what better way to get people even more excited by showing them that not only are the CPUs faster, they have less cons, such as heat which leads to noise generated by fans cooling the hot processors.