Th free upgrade Paul talks about is the upgrade from Vue6 to 6.5, I think, but I might be wrong.
I thi nk you would definitely need to buy the upgrade, but I remember last time, when you bought Vue5 a few months before Vue6 shipped, there was a very good deal for the upgrade, better than the "normal" upgrad. Dunno if it will be the same this ime, and besides, nobody knows when Vue7 will be out.