Billions of Planets Throughout the Galaxy

A recent issue of Science News noted how scientists are now estimating that the Milky Way galaxy has 100 billion planets or more.  This works out to an average of 1.6 planets per star.  And smaller planets like ours are more common than large planets.  Pretty impressive stuff considering it was only a few years back when we were seeking evidence of any planets outside of our solar system. 

The Science News article states,

To make their estimate, the scientists used data that had been gathered from 2002 to 2007 by surveys looking for the temporary brightening in a distant star’s light caused by the gravity of a body passing in front of it. If that passing body is a star with planets, the system causes a predictable boost in the distant star’s light, revealing the presence of the closer planet.

So my question now is whether this estimate would also include planets that are not circling stars.  It seems unlikely.  Last year NASA reported,

The discovery indicates there are many more free-floating Jupiter-mass planets that can't be seen. The team estimates there are about twice as many of them as stars. In addition, these worlds are thought to be at least as common as planets that orbit stars. This would add up to hundreds of billions of lone planets in our Milky Way galaxy alone...The survey is not sensitive to planets smaller than Jupiter and Saturn, but theories suggest lower-mass planets like Earth should be ejected from their stars more often. As a result, they are thought to be more common than free-floating Jupiters.

So now we are looking at 300 billion or more planets throughout the galaxy.  While we strive for Mars today, the possibilities for the future are mind-boggling.