In a world full of iPhones, playstation 3s and xboxes... What the hell does Amiga mean? 
What the hell does Android mean? Oh, it's from Google. Yeah, I recognize that.
Seriously, brand names are becoming played out. People don't give two shytes about whether it runs Windows, Windows Mobile, Android, Ubuntu, Safari, Symbian, Palm, whatever, just so long as the damned thing works.
On this I would wager a portion of my reproductive system: you produce a smart phone that works, has usable, important, and friendly features, and crashes less than once a day, built on the AmigaOS and even branded as Amiga, and people will buy it. My only lament is that I do not have the money to wager on such an endeavor.
Dealing with mobile devices day-in and day-out as I do, I have a pretty hard list of features and functions users want. I have a semi-keen idea of what developers want (really, general but a GOOD SDK.) And so on. It is possible.
OS4.1 for ARM? Too bad the XScale is pretty much dead, my Palm LifeDrive is pretty peppy with its apps (especially for the numerous reboots,) -- or is that reborn as a mobile Atom? (hrmmm, come to think of it, OS4.1 or MorphOS or AROS on an Atom-based netbook would be pretty sweet.)
Anyway, I tire quickly of the pessimistic views which immediately decry anything new with the Amiga branding as commercially DOA. Sorry if I sound like a fanboi.