I think this is a ridiculous rumor, and consider the source, PC World.
Did you ever think you could carry a portable "hard drive" on your key ring?
I don’t think it’s so far-fetched. A while back, I saw an article on some patents Apple filed for DVD drives on the bottom of laptops with swing open doors and the MacBook Air doesn’t have one built in. Clearly the space used up by DVD drives is significant and on Apple’s mind. Their non-removable battery decision also, again, suggests that the space in the case is what’s on their mind right now.