There are sandy bridge mobile quad cores out, and being Apple hasn't released the new MBP yet there is no proof they won't use one.
Usually, apple remains one generation behind from other manufacturers in technological areas like that. This is what I believe. Maybe other users here can tell what happened in similar situations in the past.
It may offer the new superduper specific technology (firewire in the past, lightpeak today and so on), but no widespread advances in new technology like new cpus, new graphic cars etc.
This is why I believe they will not use quad-core sandy bridge.
I do find it humorous that some people think the only difference between the Macbook Pro and the Macbook Air is the SuperDrive.
"If you don't want an optical drive, buy a Macbook Air! Sure, I'll just completely ignore all of the other benefits of owning a Macbook Pro over a Macbook Air!"
My predictions:
The 13" MBP will lose the optical drive to make room for a bigger battery as well as a dedicated GPU.
The low end 13" MBP drops and becomes the new MacBook. The top of the line 13" MBP becomes the default.
15/17" will both keep the optical drive. It will be like "Want an optical drive? Buy the 15 or 17 inch model". Like when Apple removed the express card slot and kept it in the 17" only.
Usually, apple remains one generation behind from other manufacturers in technological areas like that. This is what I believe. Maybe other users here can tell what happened in similar situations in the past.
It may offer the new superduper specific technology (firewire in the past, lightpeak today and so on), but no widespread advances in new technology like new cpus, new graphic cars etc.
This is why I believe they will not use quad-core sandy bridge.
I feel sad that apple chose to use dual-core sandy bridge.
To be honest, I do not know if there is quad core sandy bridge for laptops yet.
Apple are generally very quick to use new CPU tech, and very slow to use new non-CPU tech that wasn't designed by them.
Mobile quad CPUs have been available for a long time now, but the old quad generation were effectively a generation behind the duals (45nm vs 32nm). This is the first time where quad CPUs have moved from enthusiast only segments. I'd presently put them somewhere between mainstream and performance. So the MBPs SHOULD get them.