Since the recent announcement of the 4 GB Xbox 360 S model, it's been a matter of some speculation whether buyers would be able to invest in a 250 GB hard drive add-on at a later stage. Well, I say "some speculation", because it was never so much a matter of "Is it going to be available?" and more like, "How much is it going to be?".
Well, the first question's been answered, for whatever that's worth. New product images of the 4GB SKU show options to "expand your entertainment experience with Xbox 360 accessories", including Kinect, wireless controllers, and - surprise! - a 250 GB HDD.
Obviously no word on pricing yet, but expect it to be extortionate.