Here are some feature requests:
1) Need people's last names or at least last initial. for example "Scott O." is way better than "Scott". I'm already getting confused on who is reccomending what and I bet only 10% of my friends are even on it.
2) Swap Ping into the real estate that Genius takes up on the right part of my itunes screen. Way better and I bet it eventually leads to a higher conversion of sales too. I'm much more likely to buy what my friends like than pre-selected choices.
3) Maybe this is controversial, but I'd love to see anytime my friend rates a song at a 5-star level. I don't need a full album review. I want to see the songs that my friends really like. This may muck of the stream a little, but it's worth a shot.
4) iTunes needs to create a landing page for every song. Amazon already does this pretty well. I've already noticed that I want to write reviews for songs way more than albums. A landing page for each song makes firing off a review very easy and there is no conflict in the reviewers mind about whether the album deserves a different rating than the song. More Reviews = More $ for Apple & Better Music for Listeners.