You do know that all games on Plus are usually at an 80 or better Metacritic right? Knack doesn't look to be a bad game at all. Have you guys played it? It's pretty fun and challenging.
Don't really understand the hate on Knack either. I'm not even much of a fan of Ratchet and Clank or Jak and Daxter but I think Knack looks great. If you watch Knack videos in high res or see it at a demo station it definitely looks next gen. The amount of detail on Knack and all the pieces that make him up is incredible. Lighting, shadows, everything looks great and high res. It's cartoony, sure, but it's clearly something that cannot be accomplished on the PS3.