Unfortunately, it has been delayed many times because of technical issues. It even missed the planned October 10 launch recently. But we now have reports that not only is its release imminent, you may NOT want to buy one when it finally comes out.
Here's a quote from the editorial :- "The Intel X48 Express chipset and the Intel BoneTrail 2 motherboard will be the first Intel chipset and motherboard to officially support the 1600 MHz FSB. So, it might not be a good idea to buy the BoneTrail when the BoneTrail 2 is coming so soon after."
More info at TechARP.