You could almost argue that the definition of a "good programmer" is one that does know many languages, even if just to bring over paradigms from one to the other or keep his brain sharp.

I also think that programmer to architect could go either way. Some programmers are very well versed in their domain and current application and make excellent architects while the application remains the same. Once enough changes are made, they are no longer an expert in the code base, and don't know the best ways to extend and improve on it. Others are good at envisioning the current solution and know, from doing it with the programmer hat, how to best architect a change, no matter how it evolves.