For whatever reason, Racket has been the lisp that I sort of looked at last. Like many I-want-to-learn-lisp people, I went through a terrible survey of available options. I went through most of Practical Common Lisp, and then found Clojure. Recently, I've found Racket as the result of my wife deciding she'd learn a little programming via the introductory Coursera course taught in Racket.
I have to say, I'm pretty impressed with Racket. Everything from its beginner-friendly environment, to its functional disposition, to the availability of decent libraries, to its research into new areas such as type systems, everything feels very nicely constructed.
The only thing I really miss from Clojure is the syntactic support for maps and vectors, and the pervasive destructuring of said same.