I'm kinda confused on the whole thing.
I watched a video on youtube about WP8 supporting multi-cores, NFC, and 720p+ displays, even the current display which is 800x400. But WP8 added support to those stuff for new wave of devices. Now I know they've used a different kernel on WP8 and "re-imagined" windows, but in theory it should still be possible to run WP8 on current hardware.
In Apple world, iP3GS is still supported but doesn't have the same experience as iP4/S. No Siri, Retina-app support is useless. Its understandable = You need new hardware. What Apple has done to this, is to support 3GS as a low-end iPhone so people would still but it - and they still do. But as Apple brings the so-called "new" iOS 6 experience to the 3GS, its just not the same without required hardware.
But the difference is that iOS 6 is still a revision from iOS 5, only with added features. WP7 to WP8 is the kind of "new" experience. Microsoft could have chosen to bring the whole WP8 to current devices and let certain software features unusable (eg. NFC), it still could make current WP devices as low-end WP8 phones. If you're going to bash some kernel stuff into this, it doesn't matter. If an old HD2 can run 8 OS's (that is including Win 95, 98, and XP), then why not current WP devices run WP8? Is it because they're missing NFC? No 720p display? No dual-core? Doesn't matter. Microsoft could still bring WP8 to current devices and market them as low-end WP8 phones, they just chose not to because they're missing optional hardware just as what they did with HD2.
This is what I'm confused about: What will low-end WP8 devices look like? Will they have single core processor with 800x400 screen res and no NFC? Or make WP7 be marketed as the low-end WP8 phone and cause app fragmentation - being WP8 apps ≠ WP7 phones?
If someone can shine some light on me because I have no idea what I have just said, but I think you get it.