I'm a little cynical about the human race's "advanceness" (look at the stupid things we're still doing), but when you consider that we really only became modern men within the last 10,000ish years, we're not doing to bad. There's a lot of inertia in social development, so despite the highest aspirations of our most educated and/or ethical members, we're not going to achieve global peace and total prosperity in the next decade. Anyway, we're on the line between barbarism and godhood right now. We may be able to analyze the probability of other races being more or less advanced than us.
So, in a way, it comes down to what we want to believe and what we're willing to prepare for. The advanced civilizations could just be finding us now, they could have ignored us millions of years ago, or they could be unaware of us. The galaxy is a big place, after all. They could very well have forms of communication between interstellar colonies that we can't imagine. Maybe they have wormholes, gravity wave generators, entanglement intercom, string vibratronics. We don't know what's possible yet.
Personally I hope that we're just part of a family of starfaring species, with some older siblings currently exploring their closest stars and with some species just starting to probe their solar systems. It would be nice to feel at home in the galaxy.