As the use of XQuery explodes out there - thanks in large part to native support in "the big 3" enterprise RDBs - the benefits of a standardised interface to it from programming environments becomes apparent. JSR 225.
There is a direct analogy here with SAX (Simple API for XML). Just as with SAX, I predict implementations of JSR-225-ish APIs in other languages. Unfortunately from a meme propagation perspective, XQJ bakes Java into the TLA. This nearly happened to SAX ten years ago. Yes, count'em. Ten years ago.
 Oracle 11g, DB2 Viper, SQL 2005