I heard about Scala some months ago, and was pretty excited to see "a better Java than Java" for the JVM. Scala fixes a number of Java's problems with annoying boilerplate code, adds some functional programming and concurrent programming support. It has good (though not perfect) compatibility to Java's libraries, so all that code is instantly available. It's also possible to mix Scala with Java and possibly other JVM languages in the same project.
I tried to learn Lift (the Web framework) and found I wasn't smart enough to handle it. Scala syntax is very terse and cryptic in some places (where Java is wordy) and takes some getting used to. I wrote some small projects and they worked well; but bigger projects were no fun with the half-adequate support of the Eclipse plugins available at the time.
Personally, I gave up on Scala and moved on to Clojure, which offers many of the same advantages and is more (sorry to be subjective here) "fun" to program.
My personal conclusion: Scala has a lot of features crammed into it, which raises the learning curve. It feels like the complexity of C++ with the syntax of Java and the FP constructs of Ruby. I think it will be hard to persuade industry that Scala has significant advantages over Java, enough to justify the costs in re-tooling and re-training.
