especially compared to already existing alternatives. To be fair, it does have its attractions (mainly the improved bytecode language versus Java, allowing much better implementations of other languages). I think the productivity improvements come from moving up from C; the Java hypesters have been claiming similar improvements.
I'm probably being unfair, but it sounds to me that he just realized that there are good alternatives to C/C++. Then then there's stuff like, wow! A C# compiler written in C#! Well, people have been writing compilers and interpreters in the same language for decades now.
I'm a lot more skeptical about the advantages of mixed languages. Yes, it's nice to use the best language for the job at hand....except in practical terms it can become a maintenance nightmare if the maintainer has to learn ten different languages.
For example, on my current project, I'm going to try to get everyone standardized on Python for scripting, C++ for the foundation, with some VB legacy code (which may get replaced). We could use more languages (since we have COM interfaces for many of the components, and could add more), but there's no need to, and it would really complicate support and maintenance issues.
In fact, I've decided it's better if I keep all of the decision code (analagous to 'business logic') in Python because most of the good of Python (e.g. dictionary data type) doesn't survive across a COM interface. The Mono/.Net foundaton approach would probably be an improvement, but I'm not convinced it would be better than my current choice, and there's no way we'd use it now, because it isn't mature enough.
I'm also not sure that the bytecode interpreter is the right place to interface between languages.
Personally, C# is of no interest to me because it doesn't run on the stuff that interests me the most, the embedded stuff. Right now, I'd like to find a scripting language that can run using less than 16K of data and 16K of program memory and is written in C. Hmmm, I don't think even Lua is that small.
Tony