I just upgraded my NetBeans to version 6.7, and being quite lazy I didn't want to recreate all previous libraries and references, but obviously I need them. Yes, I might have decided to keep all settings from the previous version(s), which I regularly backup, but my interface had something strange and the dimensions of some widgets were quite quirky and my knowledge of the program does not go that far.
Anyway, after restoring the project I'm working on, NetBeans informed me of some missing references, just as expected.
Happy as a clam, I took the previous build.properties file, restored the lines that referred to my libraries (libs, sources and all) and... NetBeans stabbed me in the back! Still, it couldn't see the libraries!
After some restartings of the program and of the system (hey when you're working with Windows you get used to it... isn't it sad? and it often it works... isn't it sadder?) NetBeans still ignored my cries. It turned its back on me, despite all my affection steadily grown in all these years.
I gave up and recreated the libraries manually, but immediatly thereafter I checked the latest modified files in the .netbeans directory and found out what was missing... what I was missing, so actually NetBeans didn't stab me in the back so we're still in love. Yes, if you're wondering it, I had to apologize, but it happily welcomed me back.
Anyway, romances aside, when you create a library NetBeans not only adds the references in your build.properties file, but it also create an xml file in the config/org-netbeans-api-project-libraries/Libraries directory.
Should you need it... now you know!
As a sidenote: apparently NetBeans doesn't always allow the removal of different plugins at the same time, and it took me several tries to disable the profiler (actually I had to remove it, as I didn't manage to just disable it). More on the new version will probably follow, up to now I just can say that my peer likes the new colors of the splash screen.
While you wait, go get it yourself!