The New York Times has an interesting discussion of Lyme disease this week–mostly interesting for how few answers it offers.
Opossums as tick eliminators is intriguing. However, there are surely many other warm succulent creatures in the woods that ticks feed on that are less good at biting them off. So I fail to see how opossums represent much tick control. Local lore is that Guinea fowl are extraordinarily good at gobbling up ticks.