Look at some of the fan box art for Wind Waker
http://www.vgboxart.com/browse/title/5096/the.legend.of.zelda.the.wind.waker/
My favorites are
http://www.vgboxart.com/view/24067/the.legend.of.zelda.the.wind.waker/?replies=15...
We got the box art for Twilight Princess around the same day as the release date was revealed
http://www.neoseeker.com/forums/32271/t752864-boxart-revealed/
But Twilight Princess box art was shown off two months before release. for Skyward Sword there is three months left.