I just had a look at the Tegra Zone site and it introduces itself thus:
"TegraZone is the place to be for games optimized for your Tegra-powered devices."
For me the operative word is "optimized", implying that the games chosen for the site will work on other GPUs but maybe not as efficiently.
However, with a top end quad core phone, maybe the sheer processing power would make up for not being optimized. For example many PC games are optimized for nVidia graphics cards in line with the 'The Way it's Meant to be Played' programme of cooperation between games developers and nVidia, but the games still play brilliantly on high spec ATI cards, even though not optimized.
And doesn't the Ascend D Quad come with 16 GPU cores rather than the Tegra 3's 12 cores?