Big thanks for the work here folks. Just some notes below on my experience trying to flash this.
It took me a while to realize that xFSTK wasn't compiling because I was running on 14.04 64-bit. I think I read something on another post much later on about needing libusb-i386 for it to work, but that was after I had decided to load up 12.04-32bit in a virtualbox VM and it compiled just fine there. Sadly, the throughput while flashing this way was terrible and it took forever to flash the root image. I wouldn't suggest this method for others, but if you've got a sufficiently beefy host and enjoy waiting 30 minutes or more for the flash to complete here are the details for creating filters to connect the USB devices to the VM (took a little poking with lsusb and dmesg to track down the details on the last one)
Intel Edison 8087:0a9e
INTEL MERRIFIELD 8086:e005
Intel USB download gadget 8087:0a99
Resist the urge to connect the FTDI through the VM, monitoring the serial console from the host system works just fine.
Note, the version of virtualbox that apt-get installs doesn't seem to support USB so I had to download the normal version from oracle.
FAIR WARNING - In hindsight this might not have been the best idea I've had.
I ran this on an 8-core box with 16Gb ram and while my compile times were great in the VM, flashing was painfully slow.
If you're impatient and interrupt the flashing process you could possibly brick your device
If your host system chokes the VM, I'm not sure but there could be a potential for flashing to fail and brick your device.
(not sure if it would be soft-brick or hard-brick as I think that depends on how uboot is configured, maybe someone here can answer to that)
After that I was able to use Daniele's instructions to get bluetooth working.
A bit of messing about with bluez-alsa and configuring asound.conf and now I can use the edison with my bluetooth headphones.