Tegra 3 and S4 are quad core devices, one based loosely based on 4 ARM Cortex A15 the other with A9 cpu architecture with a low powered ninja core (can you guess which one is which 'cause my writing is not telling). The Tegra is from Nvidia and has been touted to have some extra 3d features; however, running viper on the DNA with beastmode kernel water splashes up to the screen on Shine Runner which is supposed to be a Tegra 3 exclusive (iirc).
Anyway the Adreno 320+ is the equal or better of the Tegra 3 in graphics even replicating extra features. I do like how the Tegra 3 can output 3D over HDMI I am not sure S4 architecture can.
The biggest difference between the two processors is from the seat of the pants feel. The S4 is much smoother without hiccups. I would posit this is from better RAM, NAND interfacing, and better out of order processing. The whole
I'd say this round goes to S4, and it highlights areas Nvidia NEEDS to address to stay competitive. The Tegra 3 needed more RAM bandwidth and better ability to address NAND quickly, Tegra needed this too as did the Tegra 2. I say this needs to change because more processing power and gpu compute power will highlight these information/performance bottlenecks further.
(I can't wait to get a Tegra 4 devices in my hands later this year.) EDIT: Still haven't seen any Tegra 4s in the wild.