For our current project we evaluated Spark and Storm, and have gone the Storm way. Personally I spent a little time on Flink, but could not convince the management for more serious consideration. Mainly because of the name recognition, Spark and Storm are so popular already. But I am confident Flink will become a great option, especially with hitting 1.0. I felt the community was very active and documentation pretty good.
I don't think it's going to be easy to move from Storm to Flink. They are very different systems underneath. Any substantially complex application is going to end up having compatibility problems.
My bets are on Apache Beam (Google Dataflow) to create that compatibility layer. Haven't used it yet, hoping it works out though!
For our current project we evaluated Spark and Storm, and have gone the Storm way. Personally I spent a little time on Flink, but could not convince the management for more serious consideration. Mainly because of the name recognition, Spark and Storm are so popular already. But I am confident Flink will become a great option, especially with hitting 1.0. I felt the community was very active and documentation pretty good.