Don't forget about Tegra 3+ which is coming later this year and is based on A15 and has 24 GPU cores with support for Direct X 11, OpenGL 4 and PhysX.
Tegra games are typically regular games enhanced with some effects and marked with "THD". It's nice to see those because no matter what other GPU phone/tablet you will buy, you will not see games dedicated for that hardware, nvidia is exception here. Sure there might be plugins to allow to play Tegra games on other hardware, but it's not certain and not without small issues. And its funny that whenever we buy non-Tegra device (like my previous phone SGS2, we want to run Tegra games so badly because they are the best looking games).
Also, Tegra 4 is already announced coming next year, so future is bright.