I have been following this project closely for a while as it is simular to an imaginary language I've always wanted (and have been slowly working on myself). Whereas Kitten comes from a Haskell heritage (thus functionally pure), mine comes from a Forth hertiage (it is a true Forth). Kitten, as it seems to me, is a potentially awesome hybrid of Haskell, C (more under the hood) and Forth and I am very much looking forward to seeing its fruition. It's about time concatinative languages got their modern, mainstream turn in the sun.