Hehe. Nice image. I think that it's not that difficult to learn the vocabulary and syntax of a programming language; but learning how to solve particular problems with it in an elegant and efficient way is another story.
Not to mention that each language (Except for general purpose languages like C) was designed to solve problems using a particular way of thinking that the designer deemed was missing from preexisting languages.
That is the tricky part for me - choosing the best language for the job!