Here is an excellent explanation of what the Xcore co-processor could do for the X1000:
The nice thing about this Xcore processor is that it has hardware mutltithreading with Quality of Service. This makes the XCore awfully suitable for realtime applications.
Todays computers are extremely weak at real time tasks. There are a lot of chips in todays PC's that have the task to buffer data until the CPU has time to process them. For example, while a Commodore 64 can do RS232 rather easy in software, a PC needs UARTs to buffer the data until the CPU has time. Basically all I/O controllers in current PC's, from ethernet, SATA, USB whatever, they just buffer data until the CPU has time to process it.
I/O would be one strength of this chip, it could process data on many wires in realtime without the need for a complex I/O controller.
Another use would be in emulators: Current emulators of C64, Amiga, whatever, work asynchronously: The emulated video controller first generates frames, and when the time is right those are shown. A chip like this could do this in real time.
Sound is another topic that would be very well suited for this chip. Wavetable synthesis is almost impossible to do right in software, because you need large buffers to prevent sound interruptions, while you want to have those buffers as small as possible to respond quickly to sound events (if you push the trigger on your joystick, you want to hear the explosion immedeately, not half a second later). This Xcore would be capable to do software wavetable synthesis just as well as in hardware.
So looking at the big picture: You get very little extra compute power, but this Xcore solves something todays computers are not good at. In fact, while the classic Commodore Amigas didn't have a proper solution, they were quite good at realtime tasks.
I think Hyperion made an interesting choice, rather than focussing on raw computer power they are targetting an area that prevent modern computers from giving the "Amiga experience".
Whether they will succeed is another story, but for anyone interested in computer architecture, this is at least an interesting development.