Is the Intel® Core™ i7-620M (2.66GHz, 4M cache) with Turbo Boost Technology an arrendale chip? Wikipedia says it is
The laptop that this chip is in also has a desecrate 512MB NVIDIA NVS 3100M with ExpressCard. i'm not sure if those graphics are more powerful than the current MBP graphics.
I am not sure if I correctly get your question. The dilemma is as follows:
Apple has only ever used integrated graphics in the 13".
With the last models they switched to Nvidia Chipsets because their integrated graphics were much more powerful than Intels (and still are).
With the new Westmere processor generation Intel refused to grand Nvidia a license to manufacture chipsets and the processors now have the integrated graphics directly on the chip.
In order to provide decent graphics performance Apple would now need to slap a dedicated graphics card into the 13". We currently can only speculate if this will happen. The leaked specs seem to indicate that this issue is not yet been resolved...