An international team of astronomers have reached the most definitive conclusion, one with profound implications: our galaxy contains a minimum of 100 billion planets. Of those, most are small planets like ours. Statistically, every star would have at least one planet.
This means that the chances of life and habitable planets in our galaxy alone is overwhelmingly high. So high that it's impossible to deny that it's out there. The only question is how much of that is little dumb critters* and how much is civilized.
According to Stephen Kane—at NASA's Exoplanet Science Institute at CalTech in Pasadena and one of the authors of the study—"not only are planets common in the galaxy, but there are more small planets than large ones. This is encouraging news for investigations into habitable planets."