As usual, I like to start with 3DMark Vantage, just because it's the gaming-oriented synthetic benchmark.
3DMark Vantage changes the weight of CPU vs. GPU depending on the preset you run. At the lowest detail Performance preset, the benchmark is weighted towards the CPU and at the highest Extreme preset, it's weighted towards the graphics card. We can see the results of this clearly, as this month's Core i7/Radeon 4850 X2 combo scores better with the lower-resolution Performance preset. But by the time we hit the high-resolution Extreme preset, last month's Core 2 Duo E8500/Radeon 4870 X2 combo takes the win thanks to the more-powerful graphics card.
This vaguely mirrors what we expect to see as a trend in most games, but real-world titles are likely to show us a much stronger preference towards either CPU or GPU power. I would guess that most of our game benches are more GPU than CPU limited, but we'll see about that in a bit.
Now let's move on to Futuremark's productivity-oriented benchmark, PCMark Vantage:
Wow. According to PCMark, the stock Core i7 920 absolutely slaughters even the overclocked Core 2 Duo E8500. These are synthetic numbers but they probably give us a good indication of how the productivity benchmarks will perform, at least in multi-threaded applications. Remember, the i7 920 is a quad-core processor compared to the dual-core E8500, so these scores probably reflect that.
Now for the final synthetic bench, Sisoft Sandra XII:
Wow again! Sandra seems to indicate a colossal advantage for the new Core i7. Frankly, this looks a little disproportionate and I don't think the real-world benches will demonstrate this level of superiority.
But why guess, let's see for real. The media-encoding benchmarks are only a page away...