There is meaning to life, very much so. The difference is between myself and a religious person is how we define it.
While a Christian may define the "meaning of life" as to live according to God and the Bible, my personal definition is really very different. In my view, the "meaning of life" is to try to get as much out of it as you can before it's gone.
My "meaning of life" is to understand the intricacies of myself and those of others. My "meaning of life" is appreciating and trying to understand different cultures, people, places, feelings, thoughts. My lack of faith has definitely led me to have a far greater understanding for myself and why I "tick," it's forced me to try to understand and interpret people and their motivations, it's allowed me to recognize the beauty in all things and derive pleasure from things most people wouldn't even notice. It's a liberation, a freedom, a kind of slowly-acquired wisdom and a never-faltering compassion for humanity-- that, to me, is the meaning of life.
I'm not trying to say religious people don't feel the same way I do, but I don't quite think it's the same thing. The meaning of my life is to live and wholly experience every moment of it, without guilt, without trying to appeal to pre-destiny, without trying to strive for an afterlife that has never been proven to exist. How can you do that with a god over your shoulder all the time? How can you do that with a pre-defined rule set in the back of your mind? Truly?
I guess maybe I operate on a very instinctual level, a lot of my values and meanings in life are quite tribal-- "living for the full vicious experience." And I think a lot of that is lost when it comes to religion trying to define the meaning of life, because it just doesn't hammer in that this one is just as important as the next (if you believe in the next, anyway).