I hope you're right, because Modern Combat 3 and N.O.V.A. 3 ran like crap on my old Sprint Galaxy S3...I mean horrible. In fact, they ran better on my old Galaxy Nexus compared to the S3, which had the exact same GPU as the Nexus S (all Samsung did was overclock the GPU in the Nexus and threw it into the Galaxy Nexus). From what I understand it's all about optimization, and because Gameloft will only have one GPU to target it could be better. I expect the games to be smooth, but they will have to cut back a lot of graphics and stuff to make them run smooth.Only time will tell, but I basically gave up on good games running smooth for the 1st generation WP8 devices. The only reason I got my Lumia 820 is because I was able to get the money to buy one off contract without having to dig into my pockets (sold a NON-STOLEN T-Mobile 810 I bought for $150 for $350, combined with selling my Lumia 900 for 250). If that luck didn't fall into my lap, I'd still be in my Lumia 900 because NFC payments aren't enabled and the GPU in the 1st waves of WP8 devices is terrible....Adreno 225 is just too weak. I know it's a good starting point to get higher end games to come, but they could have pressed for the 320...
I think that the European S III has the 320 GPU in it. All of the information is on the Wikipedia articles for both devices. The phones had the exact game SoC model number (MSM8960, I think it was?). They're both the Krait S4 with the 225 GPU. The European/Korean version has something different (quad-core Exynos CPU and Mali 400 GPU), but I have never really studied anything about cellular chips, so I don't know how a Mali 400 compares to an Adreno chip (though I've heard that the S4 is better than the Exynos, despite have 2 fewer cores).
They could have pushed for the Adreno 320, and we see it out there. The Chinese Lumia 920T has the 320 GPU in it, and I think that it was said the CPU got a boost from a 1.5 GHz clock to 1.7 GHz. It's always better to get more, but I'm thinking there just weren't enough 920T chips available for the world, and they wanted to push their top stuff to China (where there is more of an open playing field without heavy Apple intervention), which maybe resulted in the later release date for the 920T in China over the 920 in the rest of the world.
But yeah, the internals are basically the same for the S III and 920. However, if Mango vs. Gingerbread showed me anything, Microsoft's platform seems to utilize hardware more efficiently. I know 4.0 allegedly improved that to a strong degree, but my Droid Incredible on Gingerbread was a sluggish joke, while I never heard my cousin complain about chugging with his Focus or Lumia 900.
Oh, and remember that Microsoft and Nokia are pushing a pretty substantial update to WP8 this month, just 2 months after release. It took about a year after I had my Incredible before it got an update, and that was the only legitimate one it got in the 2 years I had it. Microsoft's more likely to keep things going forward on current device, as well as legacy devices.