Advantages of moving from 0.18.3 to 0.20.1?

[John Clarke]

Hi,

I currently have an app written to use 0.18.3 (cloudera ec2 dist) and it is
working fine. Are there any significant advantages to move to the new stable
0.20.1?

The app uses a custom MapRunnable to manage it's own threading.

Thanks,
John.