The Extrasolar Colonies

Mind you, there's a lot of neat stuff in the Solar System to play with before we all go through the Pandora Gates... but just for curiosity sake what are the extrasolar colonies like? Do the gates that are reliable lead to lifeless worlds, or ones that can support life? Or is it sorta like Niven's "Known Space" where the worlds can support life but the property isn't quite like good ol' Earth was? And do they have roughly the same level of technological sophistication that the Solar System has, or does the current infrastructure limited in what it can produce until larger, more settled, populations occur?