Why Hadoop MapReduce needs Scala

This is very true. It definitely helps to think at multiple layers of abstraction when writing Pig code so that you can optimize it carefully. Ultimately though, I have been rather unsatisfied with the limits to which I can push Pig. There are performance gains to be had by writing raw java code (I understand the irony of referencing java as if it was c) and there are some optimizations which you can do in Java which are relatively harder to in Pig. I am pretty excited about Scoobi though. If it does allow me to write in a more concise language without sacrificing speed or power of the underlying Hadoop API, that would be awesome.