1. It is running Cydia which is unlikely to be an easy install on a new prototype iPhone with new baseband and such. It is doubtful Apple is testing Cydia and it isn’t a cakewalk to jailbreak an entirely new device.
2. Probably most damning, it has the tell-tale old white speaker grill at the top which was phased out as the white iPhone was improved over the past year and a half. It looks like the poster may have tried to blur it as well. It is doubtful that Apple would go back to this flawed design.
Some other information that you want to transfer to you is that this machine seems to run faster than the iPhone 4, lighter weight and two glass front and back seem to have been replaced by two plastic sheets, type of sensation and cry other than the iPhone 4.
It is unlikely that Apple would ever replace the glass front with plastic. Even the $229 iPod touch is glass. Can you imagine Apple doing plastic face? Not possible.
More likely there is a matte overlay on the front of it.
Otherwise, this phone has a plastic back which would decrease the weight and cost and increase the durability. Which actually makes some sense – though the $229 iPod touch gets by with stainless steel. We were throwing this device around yesterday and concluded it was probably an iPhone 4 prototype that was brought back up to the surface – there is no shortage of those in Asia. Two more shots below.