Here's a few examples.... they couldn't just use the PS2 art, but it's a small photoshop job nonetheless.
Wii sports : http://www.thecoverproject.net/view.php?cover_id=5369
Link' crossbow : http://www.thecoverproject.net/view.php?cover_id=6034
Okami PS2 : http://www.thecoverproject.net/view.php?game_id=2056
Cover Details:
Description: Custom Cover
Format: NTSC
Created by: GRIOT
Cover Details:
Description: Original Cover
Format: NTSC
Wii Code 3456 7941 4060 2924