Not bad-looking, at least at a glance: it appears to have all the bells and whistles I expect of a current language (eg, closures, maps, first-class regex, choice between strong or implicit typing). Runs on the JDK instead of a native interpreter, and uses the Java libraries instead of the Ruby/Perl ones, but that's not a bad thing. Syntax is a blend of Java and Ruby, but tends to be pretty Java-esque. Has its own web-development framework, named (of course) "Grails".
On the downside, it's remarkably slow: the few benchmarks I've found indicate that it's 4-10 times slower than Ruby, and Ruby isn't exactly the speediest system out there. So probably not quite ready for prime time yet...