So far, the study of CMB anisotropies has allowed to reach the following well established results:
 The temperature spectrum (TT) exhibits a series of oscillations which characterizes "passive"-type fluctuations, the archetypal model for these being inflation
 The angular size of typical fluctuations allows to constrain the geometry of the universe (i.e., its curvature), which is probably Euclidean or close to Euclidean. This means that the local curvature radius is large as compared to the size of the observable universe. This crucial result is a prediction of inflation.
 The detailed structure of the oscillations in the temperature spectrum allows to have a robust estimate of the baryon density as well as the dark matter density. The two are in good agreement with other astrophysical tests. In particular, the baryon density is compatible with that deduced from the amount of light elements produced during nucleosynthesis.
 The baryon and dark matter densities compared to the critical density hint for some extra form of dark energy which could be a cosmological constant or something more strange. The amount of dark energy is compatible with what is deduced from the analysis of the lumonisity of type Ia supernovae as a function of distance.
 The analysis of the TE spectrum hint for an early epoch of reionization: although the universe is nolonger ionized after recombination, it is expected that the first stars are very massive and very hot and therefore able to ionize a substantial part of the beryons.

At present, we have a very satisfactory picture of the whole structure formation scenario. Although one might be tempted to call this the standard model of cosmology, this might be premature, In particular, we have a consistent scenario, but a number of consistency tests remain to be done in order establish it more firmly. Moreover, the description of the inflationary phase is extremely simple so that it is not clear that it is satisfactory from the point of view of high-energy physics. It is probably more appropriate to talk about a minimal model for structure formation.

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 For a more more detailed analysis, see The physics of the CMB peaks