Rebol has so many interesting ideas in it that it really could have carved a respectable niche in the world of networked programming languages. Just having sensible pragmatic built-in types for email and money was enough to bring it to my attention.
It's is a very odd but amazingly powerful little language worthy of study by anyone interested in language design. It has been a big influence on me even if I have never used it for anything 'real'.
Red looks like it's still in active development, and "heavily inspired by REBOL."
To date, Red can't even run without already having REBOL installed on your system. The project has been around for almost two years now, and only a few days ago has it successfully been able to do the program "print 1".
No one has ever built a significant business on a new general-purpose programming language. It doesn't seem to be due to the relative lack of IP protection on languages either. It may be that it's simply not a problem worth solving, there's no solution worth marrying a vendor over, or there are too many language designers.
As an aside, you can tell how interested (or not) Carl is in the future of Rebol by the fact that he's clearly not reading and responding to comments in that blog post. Otherwise he'd have cleaned up the spam comments that have been posted there days ago.
Not only that, the price point is incredibly high at $249.00. I say this as a person who actually has a REBOL/Pro license. It was never clear to me what the business model for this product was, especially since the free version of REBOL was often more up-to-date and feature-complete than the paid product.
I now look back on my experience with REBOL as some of the most fun I have ever had programming. Ever.
I have immense respect for everyone involved.