  Recently the Belle collaboration discovered two resonances, Zb(10610) and
Zb(10650), that lie very close to the B\bar{B}^* and B^*\bar{B}^* thresholds,
respectively. It is natural to suppose that these are molecular states of
bottom and anti-bottom mesons. Under this assumption, we introduce an effective
field theory for the Zb(10610) and Zb(10650), as well as similar unobserved
states that are expected on the basis of heavy quark spin symmetry. The
molecules are assumed to arise from short-range interactions that respect heavy
quark spin symmetry. We use the theory to calculate line shapes in the vicinity
of B^{(*)}\bar{B}^{(*)} thresholds as well as two-body decay rates of the new
bottom meson bound states. We derive new heavy quark spin symmetry predictions
for the parameters appearing in the line shapes as well as the total and
partial widths of the states.
