So this is basically a hypervisor -like ESX- for ARM?

Cool for developers and curious users to run a different OS and applications on their mobile device such as Symbian, BB, OSX, WM. For backward compatibility it might come in handy as well.

Different, incompatible architectures. Amiga, back in those days, had m68k (CISC). ARM is a RISC, once started by UK corporation Acorn. Together with their OSes, provided a rapid user experience. Both often used in embedded environments, before the x86-32 hegemony on desktops they were also in use on desktops. Some manufacturers -e.g. Amiga and Atari- vanished with their product while other manufacturers -e.g. SUN, Apple- went to other architectures such as -but not exclusively- ARM (also PPC, MIPS, SPARC, ...) for their newer devices (mostly desktops, thin clients, [small] servers, and some embedded as well). m68k was and is still used in embedded market, but compared to ARM relatively not much. MIPS and PPC are also still used in embedded market, but again not as much as ARM.