Given that the habitable zone of a star constantly moves chances are that far more planets can be found where water is liquid. Of course, solar events can cause a planet to shift in its orbit resulting in a planet that was perhaps too close being dragged further out in into the habitable zone. On a planet like this it would be the ideal temperature for water to be liquid, but because of the water being boiled away earlier in the planets existence there would be no water now. Similarly, if our theories on autobiogenisis are correct a planet would have to start its existence in the outer edge of the stars habitable zone for it to possible create life.
All of these are factors concerning potentially habitable planets, Of course given the sheer enormity of the galaxy habitable planets are an inevitability as is finding a planet with life. Of course, that is all moot unless we actually figure out a way to travel fast enough for such things to matter.