Twitter from Ruby into Scala and JVM: http://www.artima.com/scalazine/articles/twitter_on_scala.ht...
I think there are two aspects of a language (correct me if I am wrong) -- it's elegance/simplicity/breadth of code produced by programmers that write with it --- and then the efficiency/effectiveness/HW-optimized executable code produced by its compiler once it's run: so how does PHP and Facebook fit in with all this?