Looking at the timeline again, there seems to be gaps big enough to put other pictures. Could Nintendo be planning games take place:Drilbur said:
right in the middle of Twilight Princess and Four Swords Adventure?
right after Four Swords Adventure?
right before The Wind Waker?
right after Phantom Hourglass?
right before Spirit Tracks?
Then again, these (and the other games I suggested) could just be gaps that Nintendo wants to leave gaps.