This is a tested and rather stable new release. It has a number of performance improvements and works well on Infiniband. I've fixed issues with group Leave and Terminate and have also identified and eliminated a serious flow control bug. The promised new functionality (out of band transfer of very big files) is coming later this summer, probably in August. I'm testing with large configurations (1000 or more nodes, starting in the master/worker batch manner) and it seems to be very stable and smooth. On the other hand, I'm seeing some signs of instability when I stress-test with 2000 or more group members under heavy loads, and will be looking in to that next.