2 GHz Dual core G5 vs 2 GHz Core 2 Duo

Just wondering how the performance of a dual core G5 stacks up against the Core 2 Duo chips in most of the new Intel Macs. There really isnt much in terms of a comparison, since all of Apples comparisons were to Quad Core Mac Pros. I'm just curious since I just want a rough benchmark as to how long the machines horsepower will hold out before an upgrade is nessecary.

Thanks