Interesting slice of Tcl history.
I was forced to learn Jacl (a Tcl interpreter written in Java) in order to automate WebSphere Application Server administrative tasks a few years back. I hated the syntax. Today, I'm stuck having to use the expect interpreter (a Tcl extension) instead of Expect.pm in a Perl script. I find I still hate it. Thus, I enjoyed reading this article which I stumbled across: http://journal.dedasys.com/2010/03/30/where-tcl-and-tk-went-wrong.