Rock: I agree about "21 Guns". Just kind of underwhelmed. Franz, Muse, 311, KoL, Muse, etc - all came out with some hard ass hits. Way to recognize.
T40: Britney's "Amy" is legendary and hillarious. Also nice recognition for Rihanna, but more importantly, for Jay/Alicia. Keys absolutely slayed that chorus.
10. Eminem - Beautful Eminem made his long awaited return in 2009. The album was kind of a letdown as there was so much hype around the new album that is just did not live up to expectations. There were a few high notes on the album and "Beautiful" is one of them. It is Eminem's best song in a very long time. Seems Em is at his best when he does more serious songs.
09. AFI - Medicate Another band who made there long awaited return in 09 was AFI. it had been 3 years since they had released a new album. Crash Love was definitely my most anticipated album of the year and I was not disappointed at all when I finally heard it. The 1st single, "Medicate" is just a small sample of what you'll hear on the album.
08. Skillet - Hero I have always been a fan of Skillet and was happy to hear they were releasing a new album in 09. The 1st single, "Hero" quickly became a song that I *****d for weeks on end. The addition of Jen doing the backing vocals just makes the songs so much better. More people really need to listen to Skillet because you will not be disappointed.