To keep up with Apple, Sony may be implementing cell phone technology into the PSP. Separate to the PSP GO, the new device may not even have the PSP brand but should feature games and movies available on disc and the ability to send SMSs and make calls.
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Related: Sony E3 highlights, PSP Go rumour
I could probably go into sales for you. I am really satisfied with my PSP mobile. Definitely worth the investment.