I would suggest that the Macbook is powerful enough for most consumers. However, I wouldn't mind an BTO option for a 9600M. That's the real problem. Not enough options.
You forget that you can't just BTO anything into any notebook design.
The Macbook apparently isn't designed to handle the heat and power supply requirements of a discrete GPU.
The MBP's design can't handle quadcores or top-of-the range GPUs.
Before you cry "omg what a crappy design", think again.
The machines could never keep their form factors and weights if they had to include power hungry and hotplate BTO options.
If you think that the form factor or weight is largely irrelevant, you might be looking at the wrong product FOR YOU. Other people care about these things, and they have their reasons, right?