hmmm I've had it for quite some time now, maybe the old version grandfathered me in? It doesn't ask for anything nor do I see any registration information.
It does offer an "upgrade to Tuxera NTFS for Mac" option in its prefs pane however. It says I'm running "NTFS-3G 2010.1.16"
Try it for a few weeks and see what it says?
I work for the Department of Redundancy Department