I'm surprised that all of you didn't realize this yesterday when Aeon's design partner was announced. I discussed PA Semi based systems with Varisys months ago (they build a PA6T based CPU card). Once Aeon announced that Varisys helped design the X1000 motherboard, the PA6T was the only CPU that could be on the board on (considering the specs quoted and Varisys' design experience).
Plus, there were clues all over pointing to this for months. What other unique product does Varisys work with? XMOS processors!
Funny, everyone using MorphOS had this one pegged months ago.