Tcl is too stable for many who think the bleeding edge is cool, and too different for those who think C is the pinnacle of language design - so it's left to a large number of people who just get on with using it because it works.
Of course, if you're not interested in cross-platform GUIs, event driven I/O, Internationalization, extensibility, portability, rapid prototyping, easy interfacing to C and other languages and automated test environments then perhaps Tcl isn't for you.
See http://www.tcl.tk/software/plugin/
Tcl is too stable for many who think the bleeding edge is cool, and too different for those who think C is the pinnacle of language design - so it's left to a large number of people who just get on with using it because it works. Of course, if you're not interested in cross-platform GUIs, event driven I/O, Internationalization, extensibility, portability, rapid prototyping, easy interfacing to C and other languages and automated test environments then perhaps Tcl isn't for you.