http://www.showstop.org/images/truck/rust_warranty/dealer-communication.pdf
Page Two, Question Four, 5th bullet down. From what that states it sounds like if you are a second, third,... owner you'll still qualifie for the buyback.
I had no idea that tacoma's even had this problem. I knew that the older trucks you see going down the road with the body panels all rotted out were just typical of early japanise poor metal quality. I'm glad they've got the problem figgured out with the 2000+ models. I would be looking for 2005+ Taco anyways, but i'll defantly be inspecting the frame for rust.