In software, nothing sets my heart aflutter like new developments in Ruby/Rails-land. If all you want to do is make a quick, CRUD app, there really is nothing better, and in fact we'll see one of those new CRUD-apps (a [Digg](http://digg.com)-clone for vetting product features) next week.
I am intrigued by developments from Sun on JRuby (Ruby running as a first-class language in a Java virtual machine), and the prospect of JRuby going 1.0.
The current Ruby/Rails isn't particularly mature nor thread-safe, so using it for Enterprise-level development is basically a stretch. JRuby could make Ruby and Rails for enterprise development worth considering. It's definitely worth keeping an eye on.
Anybody interested in joining the hypefest should check out two tutorials: Rolling with Ruby on Rails, and it's successor Rolling with Ruby on Rails, Part 2.
There's a lot of leading-edge work and thinking coming out of RoR, and if you're a professional computer scientist of just a webby hobbyist it's worth your time to check it out.