The iPhone 3.2 Beta 3 SDK documentation confirmed that developing OpenGL ES on the iPad is the same as developing OpenGL ES on other iPhone devices, using the "same basic capabilities as other SGX devices."
We've been saying that the iPad was going to use the same basic chip, a PowerVR SGX, for a while now, both for compatibility reasons and because it really is just a big iPod Touch. But, to be fair, the chip is going to be newer than the ones found in those other devices, so it'll be faster. Most likely. [Macrumors]