  Among the billions of planetary systems that fill the Universe, we would like
to know how ours fits in. Exoplanet data can already be used to address the
question: How common are Jupiters? Here we discuss a simple analysis of recent
exoplanet data indicating that Jupiter is a typical massive planet rather than
an outlier. A more difficult question to address is: How common are Earths?
However, much indirect evidence suggests that wet rocky planets are common.
