Since I work for one of those authorities and it's a policy matter, I'm not going to comment on the campaign itself. But I do have some general thoughts, which are mine.
First of all, the atheists have had so much "earned media" out of this (thanks in large part to the CBC running an unverified story that they already had an advertising deal), that they can save the money they've raised and go have a taco. Their message is getting out there, and there has been the predictable backlash by some Christians against the ads, in places where they are running.
My question: why should we Christians be afraid of someone questioning God? Aren't we comfortable and confident that what we believe is so gloriously obvious that it will withstand questioning? Will our taking offense lead the atheists to revelation of the saving and healing knowledge of Jesus Christ, or will it simply be another example for the fence-sitters that proves the long-held popular view that Christians are a bunch of self-righteous, insular gits and WHO WOULD WANT TO BE LIKE THEM, ANYWAY?
I'm the sort of person who looks for the ram in the bush rather than the demon behind it, which means that, as Christians who worship a living, eternal God, we have the ability to seek out God and ask Him to turn any situation for His glory -- then stand back and let Him do it. Rather than express anger and dismay that any agency is allowing such a message to be published, we should seize the opportunity not to debate (see below) but simply to witness that the glory of God is obvious, unmistakable and unquestionable.
Why not debate? That actually falls into the WWJD category -- What Would Jesus Do? When the Devil tempted Jesus in the wilderness, Jesus never engaged him. He stood on the Word. The devil began his tempts by saying, "If Thou be the Son of God ...", and Jesus never bit. Even replying would have given credence to the notion that there was any possibility at all that He was not the Son of God, and that would allow Satan to drag the debate onto his turf -- the world.
Remember what happened when Eve tried to refute the devil's question, "Hath God said ...?": she went overboard ("nor even touch it") and by straying from the Word of God -- even with the best of intentions -- gave the devil a foothold.
So what to do?
- pray that the atheists will get revelation. Jesus wants those who are cold as well as those who are hot.
- testify. You can't beat personal testimony, so get out there and tell people what God and Jesus Christ have done in your life, and if people think you're a "good person", tell them it's all because of "Christ in us, the hope of glory"
- have a good laugh about it. How anybody can look around and come to any sort of rational conclusion that there is no God is beyond any serious consideration.
One more thing: apparently, these ads are running on buses in one city where the advertising contract is held by a company owned by a Pentecostal Christian.
Say what? Has he sold out to Mammon?
Not so fast. I've personally seen this same businessman make another decision that for a time left me scratching my head, from a Christian standpoint. And yet, in the instance I'm referring to (I won't elaborate), it turned out to be exactly what he was supposed to do. I believe he had prayed through that decision and had heard from the Lord. I believe that's what's happened with the bus adverts, too.
As St Francis of Assisi said, we should take each and every opportunity to preach the Gospel, and preaching the Gospel does not involve taking offense. It involves declaring and living and walking in the undeniable, glorious truth of Christ.
And the Light shineth in the darkness; and the darkness comprehended it not. John 1:5