C2D was only good at high frequencies (final and FSB). The lower end Pentiums and Celerons (800MHz FSB) were trash, beaten by a lot older (and cheaper) Athlon 64 X2 models. The only great good thing about them was the lower power consumption
Anyway, on topic. This is meh for us that don't worry about high end stuff. PCI-e 4 will be mostly irrelevant for a couple of years, so right now, it's just maketing to sell new boards. Unless, of course, you need a 15GB/s SSD for your work, or as
@bug says, you can do some smart saving on high end stuff with it.
I would like a new line of AM4 ITX cheap boards without chipsets please, a la AM1. A400 or A500?