Lots of pros and cons to viability of the X1000 but to get back to the interview and what it reveals to us.
Trevor said the mainboard manufacturer was a British company that had experience with ppc processors and also intimacy with Xmos. I believe that's enough info to find who the manufacturer is and thus also the processor.
Look at these links and see what you think.
Products
http://www.varisys.co.uk/products.htmland News
http://www.varisys.co.uk/news.htmlThe PA6T-1682M is the closest match to the specs quoted for the X1000 and so there could be a new variant of it and thus evaluation samples being used. Varisys does work for military and aerospace companies and so may have a guaranteed supply. The news item for March 18, 2009 provides the corroboration for extensive experience with Xmos.
It would only make sense that Varisys would want to keep this a secret until final product so as to not upset the "Apple"cart because they're using the PA6T-1682M on a competing (possibly?) platform. That would be somewhat ironic because Apple's early computers used MOS Technology processors.(That at some point was owned by Commodore) Crossed MOS = Xmos