Coldfire is NOT an accelerator it is a CPU.
Oli is designing a Coldfire Accelerator and it is not projected to have PCI slots.
As to the state of play, well the Austex effort looks a darn sight more likely to arrive in some form.
For my liking they should have gone the whole hog and popped AGA in there in the mix, made it an AGA Coldfire Amiga with expansions and PS2 ports.
Oli is starting with A3/4000 CPU card but its NOT in a working proto yet IIRC and the Austex Nueron IS booting an OS. They are far further down the line.
However, who is gonna wanna write for it? Thats where they needed to keep (or get) some Classic Amiga compatibility.