This is just out of curiosity, but how much faster is Phenom II than Athlon 64 at the same clockspeed, same core count? And for that matter Phenom II to Phenom I? Besides die shrinks, what specifically makes it so much faster clock for clock (depending on how much faster it actually is)? And also (this is just pure speculation so dont get all mad with me) how much faster clock for clock do you think Bulldozer will be compared to Phenom II?
Just look at the original Phenom II 940/920 reviews if you want to see it compared to Phenom I, it's only around 10% faster at the same clock speed if I remember right. Phenom I and Athlon II trade blows depending on application. You can also get a good idea of Phenom I vs Athlon X2 if you look up the Athlon X2 7750 reviews.
Sorry I just don't feel like looking up old articles, but I know you'll find what you need between Tomshardware, anandtech, and xbitlabs.