Languages, Tools, and the Market

The following thread on the Joel on Software's discussion forum got me thinking. Like one of the posters, I have a friend who used to do a lot of development in Smalltalk. He loved programming in the language and like the poster in the thread, praised the development tools. My question is, what makes a language "good" (good being a subjective term at times)? It seems to me that one of the main reasons that my friend and the poster liked developing in the language was not necessarily because of the language itself, but of the tools that were used to develop with. (Then again, I am not familiar with Smalltalk or any weakly typed languages so I cannot comment on that aspect directly.) But I view tools as a separate entity from the language. Any language could have tools made for it that will greatly enhance the development process. So, does one choose a language because of the language itself or does one choose it because of the tools it has? Or is it a combination of both of those factors? I also think there is a third factor which was also discussed in the thread. Does one go to where the market is? It seems to me that much development follows trends. Whatever language (or language plus tools) is currently "hot" that is where the developers go. I may love Java and wish to continue programming in Java but if ten years down the road another language is in vogue, chances are I may be programming in that language. When I was in university, one of the courses used Eiffel to teach the course. When I went out into the "real world", I told my former boss who said, "oh there's a marketable skill." And my friend? Well, he's now doing development in VB (which is ruining his programming style, he says) and intends on doing future development in either Java or C#.