Let's just say this: this generation is going to be interesting as hell.
The competition shall be fierce. I won't even be surprised if all three major areas (JP, NA, EU) all have completely different top console holders.
I expect NA to pull out Wii and 360 and butt heads continuously. I expect Japan to be overly dominated by the Wii. For EU, I expect all three to butt heads, but with Sony to be a majority winner.