Oh I FIRMLY believe there is life out there. Lots of it. Like moss growing on uncountable trillions of planets. Kepler has been finding earth-like planets almost from the moment they opened the shutter. And that's just in a tiny sliver of the sky, in a not-particularly-special part of just our galaxy -- out of more than 200 billion galaxies.
We know for sure life exists in the universe so the probability of life existing at all = 1. That dramatically increases the likelihood that it will be found wherever the conditions are similar to where it already exists (1+n>0). We keep having to expand what we mean by "conditions for life to exist" because we keep finding it in places we thought were literally sterile on our own planet. That has lead us plan expeditions to Europa and Enceladus to search for life in the oceans beneath their respective ice crusts. Earth is almost entirely rock -- it's only covered by a proportionally thin veneer of water. Enceladus, in contrast, is almost 95% water! A whole moon of almost nothing but water that nevertheless has active geology. So far, where we find heat and water we have found life.
So we have one planet and two moons in just our solar system that have a probability >0 of having life in some recognizable form. We have found more than two thousand planets -- almost all of them outside of any conditions we know life can sustain. But we've found a few that seem to favor the conditions for warm, liquid water. Jupiter is uninhabitable by anything we know of as life, but Europa is not. So of those planets we've found that can't support life, some of them may well have a moon that can.
The odds are just overwhelmingly in favor of life being scattered all across the universe on a scale we simply cannot comprehend. We are only TWO generations beyond knowing that our galaxy isn't the only one in the universe. We only just left our planet and achieved orbit in my mom's lifetime. Everything we've learned from the Voyager probes we learned in my lifetime. Cassini just raised the odds on life elsewhere in our solar system by spotting Enceladus' geology two years ago. What are we going to learn in the next 50 years? 100? 500? 2000?
I really do think we're on the cusp of publicly announcing the discovery of life of some kind. I think it will come from the James Webb space telescope or possibly the E-ELT which comes online in about 2020. One of those two scopes will be trained on the best candidates that Kepler comes up with. One of them is almost certainly going to find atmospheric evidence of life, given enough candidate planets to search.
All of that is a totally different question from: "Have we been contacted? If so, when?" I believe with zealous certainty that there is abundant life in the universe, but I am not at all convinced yet that we have been contacted by any of it. Yet. We might be really, really close.