  We review recent results for B_d and B_s mixing parameters using MILC N_f=2+1
lattices, NRQCD b-quarks and AsqTad light quarks. Latest numbers for decay
constants f_B and f_{B_s} are also presented. Combining our lattice results
with experimental determinations of the mass differences \Delta M_d and \Delta
M_s leads to an important ratio of elements of the CKM matrix,
|V_{td}|/|V_{ts}| = 0.214(1)(5) and an updated Standard Model number for the
branching fraction Br(B_s -> mu^+ mu^-) = 3.19(19) x 10^{-9}. Preliminary new
results for f_{B_s} based on other actions are also described.
