Dropping JDK1.5 is something that rears it's head from time to time, and we know we have to address it sooner or later.
We recognise that the majority of people would like to see JDK1.5 dropped, but there are still a few large critical enterprises using Drools and jBPM on JDK1.5.
Technically for us there isn't a huge advantage, and certainly no "must have" feature, in the same way that moving from 1.4 to 1.5 was. However it does make the project easier to manage: less runtime targets to test against and we don't need to double check people are putting JDK1.6 only classes in Drools and jBPM.
My personally opinion is that we need a widest audience possible for the up coming jBPM5 release and we still have some critical things I'd like to see in Drools first. So personally I'd like to wait until the last few months of this year, say October, before dumping JDK1.5; which would allow for a very late 2011 release or very ealry 2012 release that is JDK1.6+.
What do people think? Comments welcome, I've also added a poll on the right side.