Update: Edge-Online is now reporting that Analysts Michael Pachter of Wedbush Securities and Jesse Divnich of EEDAR wouldn’t be at all surprised if Sony’s next handheld supported the platform holder's proprietary UMD format.
According to PlayStation Insider (linked above), they have received a tip regarding the functionality of the upcoming PSP 4000.
Apparently it will feature the PSP Go's 16GB memory, however, it will also retain the UMD drive if the rumor is accurate.
To quote: "We received a tip today that Sony is working on a PSP-4000 that will feature the Bluetooth interface seen in PSP Go, as well as possibly featuring some of it's other features like 16GB's of internal memory, but it will likely retain the UMD drive as all of the other versions in the PSP-X000 series have.
I wouldn't get your hopes up for that second analog stick yet though, as that is likely to be put off until PSP 2 releases. You will still be able to at least use your Dual Shock 3 or Sixaxis controllers with the new PSP-4000, assuming these rumors pan out.
It looks like Sony is taking a dual market approach with PSP. The PSP Go! to combat the iPhone and Zune, with their cheap downloadable games and internally stored games allowing for pocket storage, and the PSP-X000 series for the hardcore gamer crowd that doesn't mind carrying around a case with their PSP and a few games in it."
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