Yup you are exactly right. I suppose I wasn't being clear. What I meant was there are two options. GOG can negotiate to use Clonato's Amiga Forever package or they could use WinUAE themselves and negotiate with Amiga Inc to use the Kickstart's required. The second option would be more profitable but would require more work. Also it should be noted that you don't actually need all the Kickstart ROM's just a few.
Either way the games would be packaged just as they are with ScummVM and DosBox.

Yup, that sounds about right. Well, there's certainly a market for it. I know I'd buy a lot of Amiga games, given the chance. Still, it's even more of a niche than what GOG is currently occupying, so I doubt we'll see any Amiga games here anytime soon. One can always hope, of course :-)

The one that put Jordan Mechner on the map? I second that, unless it's already included in one of Ubisoft's remakes (sort of like how Day of the Tentacle includes Maniac Mansion).
(And speaking of Jordan Mechner, while I already have an Interplay-published copy of the game, what are the chances of seeing The Last Express here on GOG?)

Pretty high if Jordan is aware of this site. Here's his board:
http://jordanmechner.com/

How did gametap do it? With emulation or with ports? I'm guessing it was emulation?
If that's the case then it might be possible to arrange legally. But probably only for very old platforms, and those games would probably have to be sold at a very low price point, or bundled into big packs to be attractive.
Technically, aren't all the dosbox games on here using an emulator?
Not sure it should be a priority right now.

Pieces of it, yes. It provides hooks to sound and graphics hardware no longer used and translates the calls to some generic OS functions that works on modern computers regardless of the actual hardware. I'm not so sure about processor instructions since the modern variants still CAN execute 16-bit code even if 64-bit Windows refuses to run it directly.
I'd call DOSbox a virtual machine (though you cannot install any operating system in it - Windows 3 and 95 may work but both are really just shells expanding the functionality of DOS, which is provided), but not an emulator.