For those who don't know, it appears that why the lucky stiff, a very prolific Ruby programmer, author, and artist (hard to describe him in brief) has withdrawn from the Ruby world completely -- all his websites and projects are gone, and he himself seems to be unreachable. So that's the big news in the Ruby world today. Very mysterious.
Anyway -- I think some of the other Ruby implementations have changed Ruby in a couple of different ways. First of all, having more implementations means having a community of implementors, and that's made discussions of features and performance and version differences and so forth very lively and productive. Also, some of the people involved in alternative implementations have also put a lot of energy into things like RubySpec, which is a comprehensive test suite designed to provide a minimum level of compliance for all Ruby implementations.
People in the community who are not actually Ruby implementors have always been involved in the process of the evolution of Ruby -- which, to put it another way, really means that Matz has always been interested in what people have to say, and in discussing the features of the language and listening to ideas for changes and additions. That's one of the things I like most about the Ruby world. Admittedly it leads to some pretty sketchy ideas being proposed now and then :-) But it also makes for a very interesting and engaging on-going conversation about the language.
Ruby training coming up in September! David A. Black and Erik Kastner team up for fast-paced, four-day Ruby intro, in New Jersey, September 14-17. See http://rubyurl.com/vmzN or contact David.