New HDInsight Content released in March:

Avro SDK  - http://msdn.microsoft.com/en-us/library/dn469975.aspx

Getting started with HDInsight (YouTube video) -  https://www.youtube.com/playlist?list=PLDrz-Fkcb9WWdY-Yp6D4fTC1ll_3lU-QS                  

Monitor HDInsight clusters using the Ambari API - http://azure.microsoft.com/en-us/documentation/articles/hdinsight-monitor-use-ambari-api/

Analyze flight delay data using HDInsight - http://azure.microsoft.com/en-us/documentation/articles/hdinsight-analyze-flight-delay-data/

Analyze Twitter data using HDInsight - http://azure.microsoft.com/en-us/documentation/articles/hdinsight-analyze-twitter-data/

Use Oozie with HDInsight - http://azure.microsoft.com/en-us/documentation/articles/hdinsight-use-oozie/

Use time-based Oozie coordinator with HDInsight - http://azure.microsoft.com/en-us/documentation/articles/hdinsight-use-oozie-coordinator-time/

More HDInsight articles - http://azure.microsoft.com/en-us/documentation/services/hdinsight/