Correct. Most people I know are using either 1.4 or 1.5 now and have no plans to change to another version (though some people using 1.4 are considering 1.5 for the future). 1.6 and later don't enter the equation. We evaluated 1.6 at a previous project and abandoned it because it's too unstable to run high availablilty systems on. It may have some funky Swing thingies but unless you're making funky desktop thingies those are useless and the stability problems are not compensated for by the miniscule performance improvement over current 1.5 JVMs.