The claim is that the weak lisp interpreter encourages work to be done in other processes (reference to the awesome Tramp), thus making the feature available to other editors (Vim, TextMate), and the shell. The author compares this philosophy to Eclipse's where everything is a Java plugin written just for Eclipse.
The claim that Emacs is dead rises from the shift in the latest versions to large included language processing plugins (JS2-Mode and Semantic) which provide rich language processing capabilities but are implemented in pure Emacs Lisp.
The author closes off by stating,
"The reason why Emacs platform is good is that it cooperates with OS, not because it is good by itself".
In other words, the Unix philosophy.