Behavior rather than belief seems to be the defining factor of the spiritual atheist. Those who call themselves spiritual are engaged in helping others, caring for the environment, enjoying the outdoors, and generally spending time meditating on central themes. We can't fault that.
No, but we can use a term that doesn't carry so much metaphysical baggage. I mean, I'm not trying to get all logical positivist wit' it up in here, but I wish empirically-minded people would think a little more about whether perpetuating the "spirit/matter" dichotomy, even as metaphor, is really what they want to do.
Besides, given that everyone and their mother self-describes as "spiritual" these days, I think it's fair to say that their behavior runs the gamut from benevolent to abhorrent, just like everyone else. I know quite a few of them who top off their all-too-human short-sightedness with an extra layer of self-absorption and a sense of divine mission that can almost make me long for the company of people who don't ponder anything more profound than beer and sports. I'm all for people being contemplative, reflective and philosophical, of course. But I will always stubbornly refuse to accede to the implication that those "higher" qualities are separate in both origin and character from the wretchedness, stupidity and suffering of the everyday world.