[lmm]

The IDE is much better than it was a year ago, in terms of stability, refactoring reliability, implicit highlighting.... It's still got a way to go, but it's there.

I don't know about SBT, I've always found Maven to be better.

Improvements to any language could be argued to threaten Scala, but most of Scala's advantages over Java still apply - better type inference, better concurrency support, case classes, pattern matching, higher-kinded types. Certainly I don't think anyone who's adopted Scala will be lured back by Java 8. If anything Java 8 seems to me to be more of a threat to C#, and especially to Kotlin, than to Scala.

I don't know about big companies, but in London startups it feels like Scala adoption is still going up.