The fifth-generation iPod touch was introduced today by Apple at a media event in San Francisco. Confirming part leaks and rumors, the new model includes a 4” display, an aluminum back with a rear flash and microphone alongside the iSight camera, and weighs only 88 grams. It features an A5 processor, and is only 6.1mm thick. Black and white versions of the new iPod touch were shown, along with blue, green, and red models—firsts for the…