I like Scala, but I'm still surprised a simpler "better Java" alternative hasn't taken off like:

http://code.google.com/p/stab-language/ (C# syntax compiled directly to the JVM)

http://boo.codehaus.org/ (Python syntax, normally for .NET, but there is a pure JVM fork in there somewhere)

The barrier to adoption these days is a robust Eclipse IDE--if either of these projects had one, I think they'd see a lot of adoption.