Steve Yegge has a comparison of various languages for the JVM. For the comparison, he creates an actual Swing application, so if the language couldn’t handle that, it didn’t get included. Since the objective was to find a language capable of replacing Java on the JVM, it’s a reasonable criterion. He’s not finished, but he goes into depth on languages he does cover. I’m sure I’m not the only one anxious to hear his opinion of JRuby. Whatever he writes about it, though, couldn’t be worse than his damning review of Groovy.
To give you a taste of Steve’s writing style, here’s something from his Java wishlist (yes, Java 5 was included in the shootout):
#2: Bean shortcuts — C’mon, Sun folks. It’s practically the first thing people change about Java when they write a JVM language (or even an interpreter like BeanShell). Even small children can tell you that accessing a property using field-access syntax beats calling a getter or setter method. The only possible explanation for why Sun hasn’t added this yet is that they hate us.