Enterprises move slowly. 2 years is no time in the enterprise world. How many Erlang programmers are there? I love learning new languages, but there are a lot of crusty programmers out there who refuse to update their skill set - and they're often entrenched in enterprise settings.

This next part will probably some change over time. Erlang is slower than Java - even with the HiPE JIT compiler. Erlang's performance is more akin to Python. Plus, as much as I protest, "enterprisey" people seem to have a love affair with static typing. They also have a love affair for nicely UML-diagrammed objects and Erlang is functional.

But the most important reason why this won't happen is that the majority of "enterprisey" systems I know of are a ton less reliable than consumer systems. "Enterprisey" has become the term I associate with needing to have a programmer on call for. This might sound stupid, but so many programmers I know worry about job security - mostly because they won't upgrade their skill set. Something that obsoletes the need for them to babysit applications eats at that security.

Erlang will get (more) popular. Lots love the functional paradigm. It's really well implemented, reliable, etc. It just won't displace Java quickly, if ever.