I think that its going to take time for the C2D to be fully realized in the MBP. Similarly I don't think we've seen the full force of the CD in the original MBP either. My money is on substantial performance gains in subsequent updates to Tiger and even moreso in Leopard. Contrary to popular belief Apple didn't just flick a switch, compiled x86 Tiger, and called it a day. 10.4.8 and its enhancements to Rosetta should be testament to this statement.
x86 OS X has been in the wild less then a year. The changes between the CD and C2D less then a couple months. The Core 2 has seriously added some horsepower to the SSE components of the Core 2. Let me quote from Apple's own marketing "stuff" on their MacBook page.
The Intel Core 2 Duo’s enhanced, 128-bit SSE3 vector engine handles 128-bit computations in a single clock cycle, accelerating data manipulation by simultaneously applying a single instruction to multiple data. That means you can get more done in less time. So, the next time you use iMovie HD or Final Cut Express to render effects, you can thank the SSE3 vector engine for the snappier performance.
Technobabble to wow your average consumer aside, what they don't tell you is that there are three units in the chip. Up from 1 in the Core Duo. Some things people are forgetting is that SSE is replacing the Velocity Engine that was found in the G3-G4. Something that allowed Apple to keep up with the Jones's in those pesky things called benchmarks. Until recently SSE was pretty much a joke until the Pentium M. Things became respectable with the Core Duo. With the Core 2 Duo the hardware is there. I t is ready but my money is on that it won't be really utilized until 10.4.9 or Leopard\iLife07.
Jobs may have declared the transition over. Don’t be fooled. The hardware transition may be done. The software IMHO probably won’t be finished for at least a year. Maybe even as far as OS 10.6. So what does my post boil down to? Even like for like comparisons such as a 2.16Ghz CD vs. 2.16Ghz C2D aren’t going to be all that accurate long term when you start factoring in OS and application updates.
