Interesting
When the discussion of ARM servers first came up, I didn't think too much of it. Maybe it would work for a niche situation like hosting for hundreds/thousands of tiny, low traffic sites... but not really game for real/significant workloads.
Looking at the roadmap and architecture direction... this could have more potential. Amdahl's law, of course, is still an issue so I can't really see ARM HPC as viable, but MapReduce... maybe?