I think you have to stop living in the eighties and, open your eyes. The Amiga is a piece of hardware and the OS is only lines of (mostly ASM+BCPL if we talk about the original 1.x OS) code.
You had a CPU, several chips specialised in graphics (copper+blitter), a chip doing (great) sound (and some I/O) stuff and a case.
Back then, PC didn't do sound (Mac was doing some audio though), had mostly text-modes or low-color/low-resolution graphics and of course not any kind of hardware acceleration.
Now, if we get back to today, what do you have in a PC ?
- a CPU (powerful, dual-core, 64bit, capable of doing SIMD, and many more)
- a (powerful) graphics chip doing many many more than any Amiga has ever done
- an audio chip (doing perfect audio stuff, even more than your ears can detect with 24bit audio,...)
- you even start to have chips doing some PhysX stuff (integrated in Graphics Boards)
Everything of course works in DMA (provided your OS has proper drivers).
Sounds very much like an Amiga to me.
So what is the difference between an Amiga back in time, and any PC (or Mac) today ? Well, as I see it, the PC/Mac has become the Amiga of the nineties. The difference is that the OS is far more powerful, eats a lot more resources, and is far more secure (even the less-secured Windows OS is far more secure than any AmigaOS). As much as I like the Amiga, I think most PC/Mac look like what the Amiga was... I don't see what difference would there be in an Amiga of today... Adding an FPGA or some XCORE chip won't make it more "Amiga"... I'm always amazed at how any graphics board today can handle dual screen and such high resolutions in 3D, true-color,... I'm also amazed at how multi-core is great... It's great to be able to run make using multiple cores, it's good to be able to have some videos running in the background without even noticing it... Hopefully CBM would have folllowed Apple and switched to x86.
As for the OS, I guess Amiga could have become MacOSX, without the elegance, cause frankly: AmigaOS has never been elegant (from 1.x versions, through 2.x, to 3.x, and this doesn't change with 4.x), nor easy to use btw: as much as I like it, AmigaOS isn't for the average user... and has never been. It was of course easier to use than DOS back in time, but not easier than MacOS (let's compare it to something that was considered easy...) and also ugly when compared with MacOS. The OS had interesting features, and really easy/clear disk layout (devs in devs/, tools in sys:tools, commodities in sys:tools/commodities), assigns are nice too and aren't to be found anywhere else.
So if there was to be a new Amiga, any good-specs PC like Mac and a powerful OS would do it. What about Haiku ? Enough modern, and enough different from other big-bloated OS... Haiku would be great. But I sure wouldn't base a next gen OS on old Exec+Inutuition libs, would be like build Windows 7 on top of DOS...
