If you compare the specs of first and second generation i7 Mobile processors, the top models of both generations are 45 watt max TDP CPUs. Moving down the line, both have lower TDP models, as low as 17 watts for Gen. 2, and 18 watts for Gen. 1. You can check the specs here:
http://ark.intel.com/ProductCollection.aspx?familyId=43402 http://ark.intel.com/ProductCollection.aspx?familyId=43402
Overheating laptops can be caused by several things. On the manufacture side of things, inadequate cooling caused by small fans and small air intake and exhaust vents. On the user side, sloppy usage by not having the PC on a solid, flat surface, instead being used on a bed or couch, or yes even a lap. Allowing dust build-up inside the laptop also contributes to overheating. Worst case situation, gaming on the laptop with it on a soft surface, blocking the fan intake vent. The cooling is so minimal in a laptop, I'm surprised they work as well as they do. That is a laptop manufactures problem, not the CPU itself. The Gen. 2 Mobile CPUs can work at higher frequencies than Gen. 1 models, with the same TDP, so they can be considered better, all else being equal.
The short answer to your question is no, but there's more to it than a simple question can address.
