I started my career with "dynamic languages" (we called them scripting languages then). I enjoy getting things done quickly with scripting languages, the power it gives you and the freedom to concentrate on the problem domain and not fight with the platform. With all the new languages that are available on the JVM alone, I'm having a lot of fun getting back to my roots. To this point I've mostly stuck to Ruby (JRuby) as I really like the syntax of the Ruby language. I've been aware of Groovy for quite some time... hearing Scott Davis and Andy Glover singing it's praises. But have just not given it enough attention... until recently.
I've been reading the Groovy in Action book from Manning. What a great title to get started with. When I get a tech book, I want to make sure it will pass the test of time... meaning: I don't want to read through it and then have to sell it or throw it away immediately due to it's uselessness. This book has a key component to it that makes it worth the money... the logical flow and organization of the book makes it perfect to work as a reference manual later on. If you are like me, you don't exactly remember EVERYTHING you read... reference abilities are VERY important to me.
With features like "FOR THE GEEKS", the layout stays interesting (as interesting as a technical book can be anyway... :) ) I also appreciate the effort taken not to go too far into Grails. Grails is very important to the Groovy language, but not everything. It's touched on in the back of the book, but just enough to give you an idea of it's potential benefit to your arsenal.