Incorrect, it probably got confused with the number of Erlang developers at Ericsson. Not all use it on a daily basis, but estimates on their developers, testers and system integrators is in that range.
Thanks, but it is not only us at ESL. Thank Joe, Mike, Robert and Jane, the OTP team and Ericsson first and foremost, and the community as a whole. It has been an amazing journey, looking forward to the next 20 years :-)
A little disclaimer on these kind words: I am just a little part of a community which has grown and evolved over the last 20 years. We are where we are today not thanks to me, but thanks to everyone who in some shape or form have with passion contributed to keeping Erlang alive and moving forward. The OTP Team, ESL employees, Ericsson at large, Open Source contributors, conference presenters, authors, commercial users, universities and research establishments and companies across all verticals alike. My role, compared to them, was minor.
Banking systems, both retail and commercial. Logistics. Embedded. Clusterware. Telecoms. Robotics, AI. When it comes to messaging, don't forget RabbitMQ and all the SMS systems.
For those of you who don't now, Francesco Cesarini is the founder and CTO of Erlang Training and Consulting, and has been a major proponent of Erlang for years, also having co-written the book "Erlang Programming" (http://oreilly.com/catalog/9780596518189 - it's a great book, I highly recommend it myself)