A quick search didnt reveal a post on this yet but scout.com has Junior year highlight tapes for Carvin Johnson. It is behind a paywall but the Link is here:
They are currently on the front page. After watching them he seems like a good player. He made a really nice one handed interception in one and had a pretty big hit in the other. He looks to be a solid tackler and he gets low and drives through the tackle with his legs. I think he is a solid pickup. But thats hard to tell from a highlight tape.