Title: What have exoplanets told us about planet formation?

Abstract: The discovery fifteen years ago of the very first planet
orbiting a solar-like star by Mayor & Queloz challenged the understanding
of planet formation based upon centuries of studies of a single planetary
system: The solar system. A decade and a half later, over 400 exoplanets
are known and countless more are expected to be discovered in the future.
With this increasing number, it become possible to test current ideas by
comparing the results of formation models to actual observations. The
results indicate that, while theory has made considerable progress, we are
still unable to reliably account for the bulk characteristics of the
population of known exoplanets. Considerable additional observational
guidance is required to constrain the models and remove all free
parameters.