So if you happen to want to look at the images inside the iPhone, that is the bunch of PNGs no image viewer will shake a stick at, now you can. Just download my bit of code from svn://svn.poop.nl/pub/iphone-fixpng. Tested on OSX/Intel. There are instances where it will break, though you shouldn't run into those with images from the iPhone.
You'll have to compile it yourself. Install libpng into /usr/local and type 'make' in a shell.
Convert the PNGs into readable files by running fixpng input.png output.png. Then if you feel so inclined to make them pretty, you can flip the R and B channels around by running something along the lines of flipchannels input.png output.png.
Update: Also tested using a PowerPC Mac, so the Makefile in svn compiles to Universal Binaries now.