I know they say it's 20Gb, but I've read a review of the system on Gamespot where they say it's actually about 14.5Gb after it's set up. I know HD's can "shrink" in size after your format them but loosing more than 25% of the space on a HD because of this ridiculous.

360 owners, how much available space was on your 360 hd's when you first set it up?