You might not need an upgrade after all but see these tests: http://www.silentpcreview.com/Small_HSF_2012/
In my opinion the "VRM Temperature" is more important to the "CPU temperature" for your CPU. Looking at the numbers, you can see which heatsinks are better than others at cooling the motherboard.
From the link, I think I'm going to pick up a Noctua NH-12L since it works very good with the single fan setup. I was debating between the NH-12L and Scythe Big Shuriken 2 Rev. B, but I think the $20 extra may be worth it for the Noctua. Now I hope it works with my video card and RAM...thanks for the article.
Temp Update: After playing Dirt 3, Civ V, and TF2 last night for a combined 3-hours, the CPU temp never rose above 62-degrees. I'm hoping everything is good to go know.