  We present new CDF results on the branching fractions and time-integrated
direct CP asymmetries for $B^0$ and $B^0_s$ decay modes into pairs of charmless
charged hadrons (pions or kaons). The data-set for this update amounts to 1
$\mathrm{fb}^{-1}$ of $p\bar p$ collisions at a center of mass energy 1.96
$\mathrm{TeV}$. We report the first observation of the $B_s \to K^- \pi^+$ mode
and a measurement of its branching fraction and direct CP asymmetry. We also
observe for the first time two charmless decays of the $\Lambda_b^0$-baryon:
$\Lambda_b^0 \to p\pi^-$ and $\Lambda_b^0 \to pK^-$.
