The first week numbers will provide more information than reports of online vendors running out of intial stock on standalone units. Given the marketing effort and build up, this is to be expected, if not through the holidays, then certainly on the initial shipments.
First week sales will give a pretty decent idea of just what kind of hardware boosts Kinect should bring to the Xbox over the holidays, which is arguably more important than how many kits they can sell to current owners. The business idea behind Kinect is market expansion and brand re-invention. I'm sure everyone is well aware of this.
It's entirely possible that production/shipping priority has been given to Kinect bundles as MS would prefer to sell consoles to new consumers than expansion kits to current owners. This would go a ways in explaining why bundles are readily available online, and kits are not.
Naturally, MS has not revealed the percentage break downs, but it's entirely possible that upgrade kits represent less than half of the overall Kinect units shipped to retail and scheduled for future shipments.
