that's just one plan. a lot of emacs people think that's a good plan, a lot of emacs people think that's a bad plan. I'm in the latter camp and prefer CommonLisp. But, hey, whatever works.
I was under the impression that while a lot of people think CL is a better plan, the work is actually under way for Guile (I guess more by the Guile team than the Emacs team). But, I feel like you would know better than I do.