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It's also possible that current technology can ONLY detect planets that are large, therefore gaseous, therefore not sustaining life.

Precisely. They detect these planets by looking at the gravitational 'tug' it places on the star as it orbits. The bigger the planet, the more noticeable the tug.

I can't believe they'd actually write an article like this. According to my eyesite, there are no other people on planet earth farther than 1 mile from me at all times, even less at night!

Bingo, the original article is bunk. We've only discovered "odd" solar systems to date because our current methods for detecting extrasolar planets are limited to detecting stellar "wobbles" or observing shifts in a stars brightness. Using these methods, it would be impossible for an observer around a nearby star like Barnard's to detect the presence of our own solar system, and yet nobody questions its existence. Why isn't it detectable? Because Jupiter is too small, its orbit is too regular, and its too far out to create the kinds of wobbles we're looking for. I believe I read somewhere that Jupiter shifts the orbit of our sun by about 30 feet, while the Earth shifts it by mere inches. These gas super-giants orbiting in wild elliptical orbits, in contrast, shift the orbits of their host stars by hundreds, thousands, or even tens of thousands of miles, which our sensitive telescopes can detect.

Detecting planets using variations in brightness is even more troublesome because it requires that the planets be A) massive enough to reflect enough light change the brightness of the host system (Jupiter may be big enough to do this...if it were closer in). Or B) That the solar system face us "edge-on" so the orbiting planets partially eclipse the central star (an extremely unlikely alignment).

As telescopes get better and we gain the ability to actually see these planets rather than inferring their presence through their effect on their solar system, we will begin to find more "normal" terrestrial planetary systems. We'll never find another Earth, of course, because we've evolved as an isolated planetary system for billions of years and our biosphere is our own, but I have no doubt that we will find Earth-like planets, possibly even with life of their own (I'm not saying intelligent life, just life).

Absolutely.
Planetary discovery techniques are based on peturbations in light output of the parent star. It takes a large and close planet to do this. So it is no surprise at all that this is the sort of planet that has been found.

It's also possible that current technology can ONLY detect planets that are large, therefore gaseous, therefore not sustaining life.

Astronomers are hoping to improve their observation capabilities in the years to come to the point where they can detect Earth-size planets.

However, they can make some tentative conclusions based on the planetary systems they have already seen, with these gas giants.

They can tell not only the approximate size of the planet, but also its orbital period and can get an estimate of its orbital radius.

With this information, they can use current general models of planetary systems construct a variety of hypothetical ones including the star and the planet or planets they have been able to observe.

I think that they have essentially concluded among the likely systems that could exist with the large planet they have already identified, in the orbit they have identified, none of them include an Earth-like planet; i.e., one about the size of Earth in an orbit producing the necessary surface temperature range.