Didn't see this posted, so thought I'd share. It's aluminum and matches the current MacBooks, so I really like it.
http://www.phonesreview.co.uk/2010/03/30/iphone-4g-aka-hd-mock-up-design-and-details-photo/
http://www.phonesreview.co.uk/2010/03/30/iphone-4g-aka-hd-mock-up-design-and-details-photo/