Lightly? I'd say one of the most important features were removed - implicits and most of the typesystem magic. Kotlin feels just like Java with lambdas, better

Lightly? I'd say one of the most important features were removed - implicits and most of the typesystem magic. Kotlin feels just like Java with lambdas, better null checking. slightly improved generics and some minor syntactic refinements. Most of its "features" will be obsoleted by Java 8.