Pentaho certification can be a big plus. Exposure towards Kettle ETL. Exposure to any NoSQL Like Mongo/Amazon-Redshift will be a big plus. Min 1.5 -2 yrs experience in developing Reports/Dashboards in Pentaho (Mandatory).
Should be aware of Pentaho BI suite including reporting, Dashboarding and ETL
Should be aware of Mondrian cube creations and MDX querying
Exposure to CDE
Aware of Mysql (or related RDBMS)
Aware of MongoDB (or related NoSql DB)