quantum mechanics - What are specific arguments against the ensemble interpretation (as promoted by L. Ballentine)?

Leslie Ballentine develops in QM: A Modern Development an interpretation based on the ensemble interpretation, and responds to most criticisms.

My question: what criticisms still exist against this interpretation such that it is not recognized as the standard interpretation within the physics community?

What problems still exist?

http://en.wikipedia.org/wiki/Ensemble_interpretation