The beauty of it Josh is that there are habitable zones for just about every star out there that is still burning. The star doesn't have to resemble Sol nor does the planet need to resemble the Earth in regards to size/distance requirements, these all change with the star being orbited.
Then you can't forget the satellites orbiting those planets, or the possibility of extremophiles on planets/satellites within our own solar system. Due to tidal warming on moons like Europa, there may be liquid water beneath the icy shell that makes up the planets outer surface. If there is, you could imaginably see extremophile forms of life similar to what you find near thermal vents at the ocean floor right here on earth.
When you add that kind of information to how many stars there are out there, the assumption that we're the only form of life in this universe seems ridiculous. Other intelligent life may certainly be out there, how and when we learn of it may certainly be centuries away just due to distances involved.
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