Though 1491 was published 15 years ago, it seemed both well-sourced and restrained in its claims. Whereas there may have been dense towns up and down the east coast in the 1400s, by the 1600s when the pilgrims arrived, and when Manhattan was sold, Europeans were encountering populations with their own politics and a societies suffering from collapses and multiple catastrophes.
1491 is generally a good book, but this was not the mainstream consensus when it was written and the information available has changed somewhat in the intervening decades. There are a lot of reasons to think that virgin soil thesis specifically is an insufficient explanation. I keep a link to Livi-Bacci's [1] essay to recommend on this topic. It remains approachable without having become severely outdated. Another good (though increasingly dated) critique is Jones' Virgin Soils Revisited [2], which unfortunately goes into quite a bit of detail about the biomedical issues with VST.
