Yes you're right, I meant to bring that up... I assumed it was just the Wii struggling to render those scenes, but it's annoying to hear it's only a PAL issue, that's just sloppy.
The sequences which played in the background during the ending credits were rather jerky/stuttered a bit for me, as though some frames of animation were missing. It was a shame that such an awesome game had to end that way, but only a minor quibble. From a bit of googling this is an issue which affects the PAL version of the game.