I think the game sold much more than 60.000 worldwide. Wii gamers are probably not the typical online gamers. I'd put the amount of gamers that makes an online acount in the first 3 days at around 1 in 5, which would mean closer to 100.000 first week, which is fine. Wii games have longer legs and I'm sure this game will reach 500k over the holidays.
This is an interesting post. You say 1 in 5 WaW owners are avid online players, correct? I'm thinking it's closer to 1 in 3, but it will be interesting to see how much the game will sell in its first 2 weeks (I myself am doubting it will break 100k even in 2 weeks).