Nah, the number 2 doesn't signify the number of Cores. The "Duo" part does. Otherwise it'd be redundant. I think Core 2 Quadro would be respecable for a quad-core Core 2, but Core 4 Quadro is just repetitive.
I'm all for Conroe. Even though that's technically not what it is, Conroe circulated as its name for so long most people still refer to it as that. It'd be easier to just continue going by Conroe; it's a cooler word, anyway.