  Theoretical predictions for inclusive semileptonic B decay rates are
rewritten in terms of the Upsilon(1S) meson mass instead of the b quark mass,
using a modified perturbation expansion. This method gives theoretically
consistent and phenomenologically useful results. Perturbation theory is well
behaved, and the largest theoretical error in the predictions coming from the
uncertainty in the quark mass is eliminated. The results are applied to the
determination of $|V_{cb}|$, $|V_{ub}|$, and $\lambda_1$.
