Concurrency is not parallelism
We have had this discussion before. This talk is illuminating.
Both the P1 and P2 are concurrent multiprocessor. I've stuck with this term, due to the subtle connotation associated with concurrency, as in multiple, different things happening at the same time, which Propellers excel at. And multiprocessor, which can express parallel execution. Combination of good ideas.
Anyway, enjoy. Great talk.