More importantly, how much will Natal cost to make.

Hmm... I'd say $79.99 with a game. They'll want to get just under Wii Fit's price (of $89.99) to try to market the price positively. However, a pack-in game is essential. Something this big without a game will flop, unless sold at a ludicriously low price, one I can't even see MS selling it for. (Say, in the realm of sub-$20.) Wii Fit helped to sell the balance board, so if MS plays their cards right, they can get Natal into quite a few homes.

yeah, needs a killer app

I think $100 - $150 with a game although $99 would be a sweet spot.

That sounds about right, change the price to $89.99.

It all depends on how good the bundled game is. If it's something which is seen as a must-have by the mainstream audience, $100 is fine. However, I doubt that will be the case, so... $80 at most?

£64.99 with a game

£39.99 without a game

100 bucks is fine. MS will make Natal seam like system launch so it can be a bit more expensive than your average game.

$80 with a good game packed in. And by good game I mean one that will be like Wii Fit or Wii Sports, or essentially a game that lots of people will want to play. If it is packed with a game that only breaks 1m units sold WW then the whole peripheral will flop.

$99 and £79.99 it will launch with a game prolly milo.