netbeans downloads it's own updates over the web

well, it is not the later version exactly. There is no 6.8.x release but Update Center contains some patches that fix the most critical bugs in 6.8 version. It is a common practice for all NetBeans releases for all platforms. If you think it is inappropriate for Ubuntu I can either switch patches off in Update Center for Ubuntu or add patches into 6.8 packages (if it won't be treated as "new feature" thing) .

I had a chat with Thierry Carrez about this. A summary:

The most critical bugs in 6.8 should be fixed in the archive. Currently just the netbeans application benefits from the builtin update;
applications and libraries found in the system using one of the library packages built from the netbeans sources (e.g. visualvm) are not fixed this way. We don't consider this a new feature, but a bug fix which should be done in time for the lucid release. More of these bug fixes after the lucid release should be handled as stable release updates.

It would be nice to have plugins and extensions in the archive as well, but I realize there always will be some of those which are not, or cannot be packaged.

Another chat with Yulia Novozhilova. The conclusion was to disable the upgrades and update to the 6.8 release branch or selected patches from this branch. The only dependency is visualvm, so a working visualvm with the changes should be checked.

This bug was fixed in the package netbeans - 6.8-0ubuntu4

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netbeans (6.8-0ubuntu4) lucid; urgency=low

  * Update Center is switched to the Ubuntu specific one (LP: #544459)
     - patches/01-updatecenters.patch is updated
 -- Yulia Novozhilova <email address hidden> Wed, 31 Mar 2010 15:19:29 +0400