Confirmation has arrived from Apple [AAPL] that says the iPad uses the same family of graphics chips found in the iPad and iPhone.
Confirmation didn’t arrive in an official document, but instead it was tracked down in the iPad SDK Beta 3 documentation. At the moment it doesn’t specify which chip out of the family that it is, but just indicates that a particular chip is there.
Using OpenGL ES on iPad is identical to using OpenGL ES on other iPhone OS devices. An iPad is a PowerVR SGX device and supports the same basic capabilities as other SGX devices. However, because the processor, memory architecture, and screen dimensions are different for iPad, you should always test your code on an iPad device before shipping to ensure performance meets your requirements.