I'm considering cutting a hadoop-2.0.1-alpha release within the next four weeks or so with some more major add ons I think we can get done soon:
# Auto NN Failover (thanks for the HDFS-3042 merge today Todd) and follow-ons as necessary.
# Pending security work for YARN (anything for HDFS w.r.t HA?)
# RM Restart (MAPREDUCE-4326)
# Container re-use (MAPREDUCE-3902)
# Multi-resource scheduling for CS (MAPREDUCE-4327).
If you would like others please set the 'Target Version' and I'll watch that list.
Arun C. Murthy