If they are indeed releasing with two versions, then it is clear as sky that the cheaper, base version would be one with just the absolute necessaries included.
Base version xbox360, no HDD, one wired controller, composite video cable and power cable included, nothing else.
From the day MS announced there would also be a wired controller available (was it a month or so ago? I think that info was linked by jvd
), to me that was a 100% clear indication that they'd also plan on launching with a retail version without wireless controllers and other "addons" including harddrive.
Why else would they've bothered making a wired controller if the basic version already had wirelesses? They could've just included the wireless controller with a detachable (usb?) cable.
Wired controller = cheaper to manufacture = to be put into the launch "stripped down" retail box.
This lead to speculations what else they could remove from the cheaper launch box... hmmm... only the removal of HD would make sense to make the retail boxes different enough in price...BINGO! There'll be two launch retail boxes: one with HD and other witout HD, no doubt about that.
I know it's easy to say "I said so" (especially as there still isn't nothing 100% confirmed by MS themselves) but looking back, and "analyzing" what MS has been doing and saying, it's been clear that MS have all the time been thinking of launching with two versions; the vagueness in comments for backwards compatibility, No inbuilt WiFi, The HD being so very external to the design for easy installation, even the two versions of "Live", ..... the much talked about "customability" and "personalization" of your xbox, that is not just the faceplates, but being able to "build up" the base model to meet your needs... the
fact that you can strip down the xbox360 so that there's very little of extra accessories, which can although always be very easily installed later by the customer.
If a company is to launch with two versions, there's no sense for any company to release versions that are very close together price and "included accessory"-wise. It's always the cheap(er) very stripped down base version and the other which has one or two bigger accesories and is about $150-$200 extra.