I am a loyal Norton user going back to DOS - and I am royally ticked at Norton right now.
The subscription on my 3 home PCs expired Sunday. Last week I was on the verge of buying the renewal at $49.95, when I got an offer from Costco for NIS 2010 Netbook Edition for $19.95 delivered, covering 3 PCs for one year. After verifying with Norton that this contained the same features as the "regular" NIS 2010, I ordered it. The box arrived Saturday, the last day of my subscription. I immediately installed it on one laptop. The install went flawlessly. I was busy with other matters until today (Monday) but I didn't worry about my two other PCs which are always on and online, because based on past experience, I figured that even though the expired subscription would no longer download updates to them, they still would have the existing NIS protection level as of the cut-off date until I could install the new Netbook Edition on them.
Wrong. 
When I went to my desktop this morning to load the N.E., I found that the previously installed NIS 2010 was turned off. Not off as in "no updates since yesterday" but totally disabled. I verified that not only was NIS turned off, but the Windows firewall, which normally is turned off by NIS, had not been reactivated when NIS said buh-bye. This was a complete shock because in early versions of Norton a lapse in the subscription merely stopped the updates but left the installed protections working, using the last installed updates. (This was standard practice then for any software with an added update/subscription service.)
So... two of my computers were online for more than a day with NO protection whatsoever. Right now I'm running a full scan using the N.E. version and hoping that no malware slipped through while NIS was AWOL. This is inexcusable behavior from a top-notch security vendor like Norton.
There was nothing in any of the pop-up renewal notices that all of NIS would drop dead along with the subscribed updates. At the least, they all should have contained an additional warning that unlike some previous Norton versions, expiration would mean a total cessation of the installed NIS suite of protections. Maybe Norton took it for granted that the meaning of the advisories was obvious, but they were not obvious to this long-time loyal user. (And while I'm at it, NIS could have at least exited gracefully by reactivating the Windows firewall.)
I am posting this here to advise other users of this "feature" in their NIS. Don't let your subscription lapse even for 24 hours as I did or you'll get a nasty surprise. I understand that subscription renewals are an integral component of NIS - they are the "blades" to the NIS "razor"- but to leave me unprotected like this without adequate warning? How am I supposed to trust Norton after this ill-advised breach?