Tokyo Game Show we started hearing new reports of the PSP2, a device that's been rumored since roughly the dawn of time (which could explain the prehistoric creatures on the concept render above). These rumors, however, were different, specifically the mention of a touchpad on the back of the device. Alas that device didn't make an appearance to the press at TGS, but supposedly Sony was showing it off to some developers. Kotaku has learned a few more things, most notable being a display an inch larger than the current PSP's and having a high-def resolution -- a detail that should surprise none. According to the report Sony is still tweaking the internal hardware, trying to mitigate overheating issues ahead of a release sometime in the fall of 2011. That would likely mean an unveiling at the 2011 E3, the same place the original unit was first shown in the flesh eight whole years earlier.