Why do I need to register to submit a bug!?
There are a few reasons, but the most important is to ensure we have a valid email address.
The majority of bugs filed do not include enough detail for a developer to find and fix the issue. Users routinely do not mention what OS or JVM version they are using, let alone build # of NetBeans etc. So developers investigating those bugs have to reply and ask for more detail. Without a valid email address, there is no way to get that extra detail, the bug can't be pursued and has to be discarded - but developers still have to plough through incoming issues evaluating which can be pursued and which can't! Requiring a registration ultimately improves the quality of incoming bug reports.
Another reason to require a registration is to prevent abuse of the database, or at least make it a little harder to abuse. People interested in submitting junk data are not likely to want to bother if a registration is required.
Many major open source projects require registrations to file bugs (eg Mozilla, Gnome, OpenOffice ...), and all for the same reasons.
Well written bug reports are one of the best ways you can help, so please don't be put off by the registration requirement.