The cat may already be out of the bag in terms of what the next iPhone will look like, but questions are still swirling as to what’s inside that flat, glossy shell, not to mention the sharpness of the supposedly revamped display.

Engadget speculated months ago that the upcoming — and now thoroughly leaked — fourth-generation iPhone might in fact be dubbed the iPhone HD by virtue of a new, higher-resolution display, and now Taipei-based tech site Digitimes is backing up the claim, reporting (based, as usual, on “sources from Taiwan-based component makers”) that the next iPhone display will boast a resolution of 960 by 640 — twice that of the current iPhone 3GS.

Digitimes (which, like many other sites when it comes to Apple rumors, has a spotty track record) also claims the iPhone’s revamped screen will work better with e-books thanks to FFS (fringe-fiend switching), a display technology designed to make mobile screens easier to see at wide viewing angles and in direct sunlight.

Another interesting (if only purported) detail from Digitimes is that the iPhone’s new display will be 33 percent thinner than previous models’, which would make room for a bigger battery — nice, although keep in mind that thanks to the power demands of the soon-to-be-released, multitasking-capable iPhone 4.0 OS, the next iPhone’s actual battery life might not be any greater than that of the current 3GS.

Digitimes also claims that hardware manufacturer Foxconn is poised to ship 24 million next-gen iPhones starting in June, which would coincide nicely with the June 7 keynote for Apple’s annual Worldwide Developer Conference — the likely venue for a new iPhone unveiling. Apple usually starts shipping its latest iPhones a few weeks after announcing a new model, so it’s certainly possible the next iPhone could go on sale before the end of June.

Of course, much of the mystery surround the next iPhone has already been spoiled thanks to leaks from Gizmodo and, most recently, a Vietnamese tech forum, which have described a new, flatter, thinner handset with aluminum edges, an A4 processor (same as on the iPad) and a front-facing camera.

And as for the Verizon iPhone rumors, well … who knows. A rumor last week had it that Apple had awarded a contract for a CDMA iPhone (which would work on either Verizon or Sprint) to an overseas hardware manufacture, while another rumor claimed that a marketing firm was already hard at work on an iPhone ad campaign for Verizon. But Verizon promptly poured cold water on the iPhone rumors by announcing it was working on an Android-powered tablet with Google that would compete with the iPad, making an iPhone partnership with Apple look far less likely.

So, would an iPhone with an improved, double-resolution display and a front-facing camera tempt you to trade up? Or will you wait it out for a Verizon iPhone?

Via Yahoo