I recently got an iTouch to dev on. I have my toolchain up and going and am working on a few projects for this very powerful handheld.
iPhone software can be used on the iTouch and vise versa. Not only does this iTouch handheld support a really nice hi-res touchscreen, but also OpenGLES video hardware acceleration, but also a powerful 533MHz ARM11 CPU based on the SAMSUNG S3C6400 SoC!

read it here zodttd