Ok here is my geekbench results for my iMac 27" 2.93 ghz i7 To give you a comparison, I ran it in both windows xp 32 bit, and snow leopard 32 bit. I also ran snow leopard 64 bit. http://browse.geekbench.ca/user/v604mustangjoe/profile you can also see my C2D macbook pro on here as well (mid 2008 model). As you can see snow leopard 32 beat windows xp 32 bit on the same computer, and 64 bit snow leopard is definitely worth the upgrade. 32 bit snow leopard beat 32 bit xp by 1000 points, and 64 bit beat 32 bit snow leopard by another 1K + points. My friend has a newer mac pro at his work and it barely beat the iMac i7.