What are the odds that those coincidences all lined up, and, given the number of planets in the Universe, how many of them are like ours? (Drake, of course.)

What are the odds that those coincidences all lined up, and, given the number of planets in the Universe, how many of them are like ours? (Drake, of course.) Given the sheer size of the Universe, I'm personally not too surprised, but that's just gut-feeling.