SUMMARY: Of the 130 extrasolar planets discovered to date, most have been found using the radial velocity method, where a planet causes tiny changes to a star's velocity compared to the Earth. This back and forth motion changes the wavelength of the light from our perspective. Another method, the transit method, has turned up 6 planets so far, and should find many more in the coming years. It works by watching for a star to dim slightly on a regular basis as a planet passes in between us and the star.

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The problem with both techniques is time. I could look at a star for a decade and see nothing, but then the next night the transit occurs. I could look at the radial velocity just the same, and only have the curve finally jump out after years or decades of observation. The reason the planets we've found are almost all in tight orbits and the planets are huge is because the techniques we used are biased toward these objects. And of course the transit method is the most biased of all because the orbit of the planet has to be almost perfectly aligned with our view of the star for it to be detectable, so although we will find world's this way, I doubt it will be many.

Until we get a SIM or TPF like mission up and running, where we can look at a star and see the world's orbiting it, we will not get much beyond the Hot Jupiter phase of planet hunting.

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...and we'll be saying a big hello to all intelligent life forms everywhere; and to everyone else out there, the secret is to bang the rocks together, guys...

Agreed, though as long as we stay aware that the planets we ARE detecting represent a biased subset, we can be careful to not draw crazy conclusions from what we are seeing.

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Forming opinions as we speak

It seems to me that we're not doing that, though. That large core planet was described as clinching the planet formation debate when it was only one example out of less than 200. I think we need to wait until the population of known planets is several thousand, including planets from the Hot Jupiters to out to about 30 AU and for stars out to a few thousand light years away before we begin trying to say for certain how planets formed or try to support any other planetary theory.

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...and we'll be saying a big hello to all intelligent life forms everywhere; and to everyone else out there, the secret is to bang the rocks together, guys...

I wonder how many we will find by 2100