First, I am about as conservative as you get. Inerrantist; salvation by grace alone, through faith alone, by Christ alone. Vocal against the heresy known as Roman Catholicism … and on and on.
But I have to say that those who attack Rick Warren remind me very, very much of all the attackers of Billy Graham through the years. When God is using someone powerfully, the attacks come from the right and the left, with a lot of erroneous information.