Improved toolchain to minimize complexity:

- better compiler error messages:

https://raw.github.com/scala/scala/master/test/files/neg/fou...

https://issues.scala-lang.org/browse/SI-2388

https://issues.scala-lang.org/browse/SI-3092

(unfortunately the JIRA is down now and google didn't really cache them)

- compiler warnings, e.g. tupled arguments:

https://issues.scala-lang.org/browse/SI-4851

- implicits: "-Xlog-implicits" switch tell you where they come from (and the IDEA plugin works pretty well on this issue), and explicit return types for implicits:

http://groups.google.com/group/scala-internals/browse_frm/th...

- documentation: definitely a lot of work with a "doc czar" appointed.