@Mandoble
I disagree on your main argument there. RAM is definitely a critical resource and it is responsible for the "fluid gaming experience" (as I said) however we've gotten the point where RAM is both ridiculously cheap and in abundance. You aren't going to get that much more out of a modern system by putting a heap of RAM in it, especially for a single task device, because you can pretty much afford to put as much as you need in there without breaking the bank. Especially if you don't have to worry about power consumption!
When you think about it @Sony_70 was kinda on the money before in a strange sort of way. Mobiles have 1GB RAM these days and for that reason I think it's fairly safe to say we don't live in a RAM limited world anymore. We aren't talking high end multitasking devices here we're talking call, facebook and watch videos devices and they're putting 100s of MBs and even upto 1GB of RAM in them and handing them out for ~$100-250AU a pop.
I struggle to see a reason why the Wii U would need that much more than 1-2GB of RAM but I don't see why it couldn't (even though obviously it would be faster and more expensive than 2012 often DDR2-ish phone RAM!). At the same time I wouldn't be going nuts if they surprised us all and revealed it has 8GB because I don't think it would make that much of a difference. Not with the CPU and disk being the limiting factors and not with this 1080p single or at most dual task game console world it's going to exist in.