NAV 2004 has beloved software activation.
The entire 10 second process is such a non-issue for legal users. If that is your sole consideration for not buying a piece of software, grow up. The fact is, unless and until everyone uses Linux and all it's free options, more and more software is going to use an activation scheme. Again, this is such a non-issue unless you are the type of person that prefers to steal their software.
[EDIT]Oh, and I don't think there is much of a compelling reason to spring for the new version over renewing 2003. Unless you can get 2004 for about the same price of resubscribing. The Spam protection is pretty good, it works well with Outlook 2003. It has found about all the spam that comes into my inboxes but I bet there are other tools that offer more options. Though I honestly don't recall if that was a part of the NIS package or NAV, so this may not matter in your case. So long as they continue to provide virus defs, stick to 2003. Unless, like I said you can get NAV 2004 for around the same price. In that case, why not.
\Dan