@OP: if they use a Power CPU, a legacy Broadway CPU isn't needed for BC.
About RAM: MINIMUM 2GB, to be reasonably sure multiplats are possible without the need to modify the levels or the way they are loaded. Hadn't MS still stuck with 32bit instead ot completely switching to 64bit, keeping 3GB the maximum requirement of most PC games, the minimum RAM also for next gen consoles could have easily become at least 4GB. It's true that Windows is a resource hog, while consoles have lean OS', but this can lower their main RAM requirements for the same games only down to a certain limit.
I agree about the complete set of motion controls, both hands-free and with controllers.
Quite obviously Ninty must also add some original HW features carefully taylored around the gameplay innovations it wants to bring, unless Wii2 be only meant as an evolutionary step of Wii, in this latter case Wii2 would be a fitting name.
