Thoughtworks [1], an industry leading company, has upgraded Scala to "trial" status in their Technology Advisory Boards recent Technology Radar, [2] an advice to clients in which emerging technologies to invest. Their reason for doing so they say is "we have realized that the wider applicability of Scala makes it more approachable for enterprise developers" and "we have witnessed great successes in the adoption of Scala."
ThoughtWorks is a global IT consultancy with over 1,500 professionals providing Agile-based systems development, consulting and technology advice to Global 1000 companies. It is regarded as a pioneer and leader in Agile software development. It is considered to have some of the best practices used in the industry today.
Now they rate Scala as "Worth pursuing. It is important to understand how to build up this capability."
Links:
[1] http://www.thoughtworks.com
[2] http://www.thoughtworks.com/sites/www.thoughtworks.com/files/files/thoughtworks-tech-radar-january-2011-US-color.pdf