Looks really interesting and not another SQL on Hadoop solution. The benchmarks look impressive, but all of the queries were aggregations of a single table. I did not see any joins. I wonder how mature the optimizer is.
I think it's because the docs say "If there isn't enough memory, you can't run a JOIN." . While SQL on Hadoop solutions work also without enough RAM by spilling on disk. I don't think a comparison with JOINs would be fair in this case.