Please tell us the future of CLIPS.
Version 6.3 will target rule performance, improved integration with other languages (such as C++, .NET, and Java), unicode support, and examples for common use cases. Some of these features are available in the current 6.3 beta. No release date is set.
Will CLIPS be supported under UNIX (in my case SunOS and Linux)?
It's always been supported under Unix. Just compile the source using gcc.