Thom,
I have not set a specific upgrade policy, but at the moment I'm looking at a discount for all registered users as well as some kind of free upgrade period for those who purchase near the release date.
At the moment I don't have the release date nailed down either, but it is still going to be early 2010 at the earliest. I still have quite a bit of work left to do.
My guess is that you will get more than your money's worth by the time we release the major upgrade. Also, there is nothing that will expire on the current version so you can use it as long as you want before deciding whether to upgrade.
VR
Brad