It would be hard to have escaped the fact that the iPad is powered by the much lauded custom A4 processor which is a ‘system on a chip' – a single Cortex A8 core paired up with a PowerVR SGX GPU. The units are sold in 16GB, 32GB and 64GB versions. Onboard we also have 802.11a/b/g/n WiFi, Bluetooth 2.1, an accelerometer, microphone, digital compass and ambient light sensor. The 3G model is also now shipping in America for around $100-$120 extra than the basic wifi model.
For a really detailed look at the insides, check out the ifixit article over here.
Amazing to pull out one of these and surf the web in silky smooth 3G