I like the Buddhists I've met. They seem to be nice people who subscribe to the notion of trying not to hurt other people. But my limited and flawed understanding of Buddhism is the philosophy that life is suffering and nothing is permanent (both of which I agree with) and that we are reborn multiple times and the objective of life is to end the cycle, achieve enlightenment, and not be reborn anymore, none of which I agree with.
If you remove the whole reincarnation and enlightenment thing, can you really call it Buddhism any more? What is meant by "spirituality" if not an assertion that there's something outside the material world of physics?
If a person thinks that Jesus was a cool dude, and agrees with his ethical teachings, but does not believe in God and does not believe that Jesus died for our sins or that he was resurrected after three days, can that person reasonably call himself a "secular Christian"? Well, he can if he wants to, but I would disagree with the label. (Caveat: The Marcionites believed that Jesus didn't actually die, since they reject the doctrine of the dual nature of Christ. But they do believe that he was God and the Savior and that he absolved us of our sins. But the Pauline Trinitarians wiped them out, as they wiped out all other competing Christianities. In any case, they certainly were not secular.)
I like "secular" Buddhists just as I like regular Buddhists (and Wiccans, for the same reasons) but I think they're all nuts, as far as their rejection of science goes. I suppose a skeptic who believes in being nice to people and trying not to cause harm to others might choose to call himself a secular Buddhist, and I would not disagree with him about anything other than the odd choice to use a term that is ambiguous if not actually contradictory.