OK, the development environment is interesting and the implementation sounds good. Eiffel is a nice language (somewhat quite verbose, but in return also considerably more readable than, e.g., C++). And through the integrated tools, such an environment naturally offers more than just a bare compiler - CASE tools etc. are included.
Nevertheless, in my opinion, the price of 4800 US dollars is rather an argument against buying it. Sorry folks, but for that price I can get a fully equipped license for Allegro Common Lisp, and it offers considerably better comfort and considerably nicer language features and expressiveness than EiffelStudio.
And I find the price for Allegro Common Lisp already considerably too expensive...
At The Macintosh News Network there's the original article.