If it claims to be distributed and its not written in erlang, don't use it.
Well, that's the filter I use when looking at anything. If its not written in erlang I spend a lot of time trying to figure out exactly how it isn't really actually a distributed system. Usually I find out that it isn't.
While I generally agree with you, there are some applications out there that get distributed multi-node environments "right" without using Erlang. It's just much harder to do because those problems are (for the most part) solved BY Erlang for the programmer.
If something says it is parallel this, or concurrent that, that is when I filter it - thus far Erlang's concurrency model has been unmatched (in my limited experience) by any other language I've used for efficacy and simplicity.
That's an extremely crude filter. A lot of the best distributed system stuff is built on the JVM. Too many to name, but I'll name one anyway: Zookeeper
Well, that's the filter I use when looking at anything. If its not written in erlang I spend a lot of time trying to figure out exactly how it isn't really actually a distributed system. Usually I find out that it isn't.