The Cosmic Microwave Background and Observational Convergence in the   Omega_m - Omega_lambda Plane
  I use the most recent cosmic microwave background (CMB) anisotropy measurements to constrain the leading cold dark matter models in the Omega_m - Omega_lambda plane. A narrow triangular region is preferred. This triangle is elongated in such a way that its intersection with even conservative versions of recent supernovae, cluster mass-to-light ratios and double radio source constraints, is small and provides the current best limits in the Omega_m - Omega_lambda plane: Omega_lambda = 0.62 +/- 0.16 and Omega_m = 0.24 +/- 0.10. This complementarity between CMB and other observations rules out Omega_lambda = 0 models at more than the 99% confidence level. 
Charles H. Lineweaver (UNSW,Sydney)