What was the attach ratio and total sales of the Eyetoy/PS2 (might be a fairly good indication of ARC's potential total sales)?
With Natal, I know Microsoft will market the hell out of it, but who will they market to is the big question? I think they will have a real hard time rebranding themselves and selling it to the Wii owners/crowd, which means in the end how well it's implemented in shooters and sports games will determine it's success (based on their current install base and branding).