<disclaimer>I really like Groovy and other cool languages like Scala, Fantom, Gosu or Clojure targetting the JVM.</disclaimer>
I know the title is a bit provocative but I want to express a concern regarding Groovy++. In my perception most people think of Groovy++ as an extension for Groovy which trades dynamic dispatching for static typing and dispatching yielding performance. So you can just look for hot spots in your code and resolve them with some annotations. Sounds nice, doesn’t it?.
That seems to be the promise of Groovy++ but it isn’t. Alex Tkachman, the founder of the Groovy++ project states this clearly in this comment to an issue with Groovy++: “100% compatibility with regular Groovy is nice when possible and we do our best to keep it but it is not a must.”.
Imho the mentioned issue together with this statement reduces the target audience to a few people who think of Groovy++ as a better Java, not a faster and type-safe Groovy where needed. I do not think there are too many people thinking that way. I think wide adoption of such a Groovy++ will not happen given the alternatives mentioned in the disclaimer above and Groovy itself. I hope they will strive for 100% compatibility with Groovy…
Schneide Blog 
Actually the target audience for Groovy++ is much, much bigger than Groovy. I love Groovy, but the vast majority of developers aren’t going to be giving up their static types. Groovy++ almost gives us the best of both worlds. The static safety, speed, and potential IDE-awareness of Java, and the expressiveness of Groovy.
Groovy++ is a very, very young language. A proclamation of it being doomed is premature.
I never saw it that way. Thanks for the insight!
I absolutly agree.
Groovy++ could be much better and popular than Groovy.
For static typing just use IDEA and its joint compiler.