From Ruby to Scala?
qhoxie: These are surely aspects that differ based on the coder, but here is my take on it.  I have a strong Ruby background and the last few months I have been using Scala alongside Ruby.1.  In short, yes.  I think the key for me is using a mix of Scala and Ruby.  For many tasks, I am not as efficient with Scala.  I think that is 2/3 my inability to more effectively leverage the language and 1/3 the language itself.  I find Scala to be incredibly clear; in many cases more so than Ruby.  The type system and pattern matching can do amazing things for readability.2.  The Artima book is helpful to have at hand, for sure.  As for getting up to speed, both the O'Reilly book and the Pragmatic book are good.  Just from my feel, the Pragmatic appeals more to those coming from a Java perspective, and the O'Reilly appeals to people with a Ruby/Python background.3.  Never built more than a toy application with Lift, but there are definitely a fair number of people using it in production.