Well, again, pre Hyper 212 Evo, I idled at stock frequency around mid 40's. post 212 installation gives me about a 30C idle temp and 42C load temp with a 450Mhz OC as well. I must say, I'm pretty damn happy with the purchase. You guys all knocked it out of the park on this one.
Thinking of using on of my case fans as a second Heat Sink fan.
If you use one of your case fans on the heatsink to create push/pull airflow you will notice even better temps. Possibly much better.