Why, 3D, of course (as the title says).
The processor used in the tablets is an OMAP2 ARM(EL) processor manufactured by Texas Instruments. This chip is used in a wide variety of mobile devices and is a "packaged" chip meaning it's not just a CPU. It's a CPU with onboard ram, included video chip, 3d accelerator, hardware mpeg processing, java bytecode interpreter etc. However, not all these features are used on every device. On our tablets, the 3d and the video chip are not utilized because they don't support a screen of the resolution the tablets have. The LCD is handled by a third party (Epson) chip. Also missing is drivers for the hardware Java interpreter (Jazelle) but this is due to a licensing issue if I remember correctly.