Atheist Billboard: Attack or Innocent?

We all have different beliefs, that's fine. We are all free to believe what we want. However, I draw the line at open attacks. This is an attack. Question:

If Christians are accused of "forcing" their beliefs on you when they say "I don't agree with (insert controversial topic)", what then is this billboard?


If the answer given is "free speech" then please accept the title of "Hypocrite".