  We present results from a calculation of the transition temperature in QCD
with two light and one heavier (strange) quark mass on lattices with temporal
extent N_t =4 and 6. Calculations with improved staggered fermions have been
performed with a strange quark mass fixed close to its physical value and for
various light to strange quark mass ratios that correspond to light
pseudo-scalar masses in the range (150-500) MeV. From a combined extrapolation
to the chiral (m_l -> 0) and continuum (aT -> 0) limits we obtain for the
transition temperature at the physical point T_c = 192(7)(4) MeV.
  We also present first results from an ongoing calculation of the QCD equation
of state with almost realistic light and strange quark masses.
