Speaking unofficially; the unit is not released, so formalized info is sometimes scarce.
No emulator is needed per se (though coudl be handy, it is unlikely in practice.) Just install your favourite Linux distro and go from there (or set up a VM with an angstrom derived installation to be closer, still.) Most games will porbably be SDL or X11/etc based since that gives you a very high compatibility across distributions. (Of course, you can read the GPIOs diredct or go to the metal if you like, but this stuff isn't heavily publicly documented yet.) More to point.. if you coded to the specific hw and have no device, its not really useful for testing
So for now, abstract your input handling and wrap it around SDL or whatever you use for your native Linux install, and then for shipping Panda's swap in or #ifdef in the appropriate code; we'll probably have libraries for everything you need.
(ie: We're generally going to support straight to hardware, SDL and X11 as interfaces to input, output, etc.)
There shoudl be a link to the pandora GIT where you can obtain the kernel source and various sources we're working on.
The touchscreen should be typical .. take a look for tslib and such, like other Linux distros.
jeff