The first of these gulfs is between Humanism and antitheism. If Secular Humanism accepts that supernatural religion subverts human dignity and that non-supernatural religion is obscurantist, can Secular Humanism credibly distance itself from antitheism? The only basis I can see for the Secular Humanist aversion to antitheism seems to be rooted in ad hominem anecdotes of antitheists who go too far. Unless you've crossed the line into coercive repression, I don't know how you could go to far in deriding religion. It seems to me that Secular Humanism has all of the philosophical antipathy toward religion that characterizes antitheism, but chooses alliance with the religious left over open derision. One might rationalize that our religious allies harbor an equally veiled urge to evangelize us, but I suspect their beliefs are of the obscurantist, non-supernatural or undifferentiated variety if they call themselves progressive.
The second gulf that Atheism+ proposes to bridge is between social activists from the freethought and religious communities. That gulf is already bridged by Humanist/Interfaith cooperation. Those who oppose religious privilege, whether they come from freethought or religious communities, already have the option to embrace the secularist label. Secular humanists have natural allies in progressive faith communities on issues of social justice. Religious and atheist secularists can agree on a vision of religious freedom predicated on freedom from religion. Religious allies who reject prejudice against atheists are also our allies in the struggle against theonormativity and skeptophobia.
Humanism and secularism have established common ground between believers and non-believers on issues of social justice and religious freedom, respectively. The Interfaith community also shares atheism's regret over sectarian enmity. The area where there will never be common ground is between people of faith and antitheists on the issue of religion's role in undermining human dignity. Atheism+ proposes to set firm boundaries with our religious allies. I would offer the suggestion that they draw the line this side of theonormativity. Religious social justice advocates who bolster the faith-in-faith argument betray themselves not only as obscurantist for extolling the virtue of faith independent of a concrete truth claim, but also as theonormative for the presumption of faith as a universal value and skeptophobic for the invalidation of non-belief.
A great thinker from a time before the advent of a new wave can only be seen as a precursor in retrospect. Nomenclature has a way of catching up to genius. Hype, on the other hand, can turn a ripple into a wave that inevitably loses momentum. If Atheism+ is a forced category rather than an organic one, it could ultimately be seen in the context of a movement flailing about for meaning. Only time will tell whether or not Atheism+ will ever become historically, politically or intellectually significant. It has the intellectual heft behind it to propel it toward significance, but the time for activism is now. We don't have the luxury of waiting for history's verdict. Dismiss the label as a passing fad, or as atheism minus objectivism. Embrace it as an approach rather than a movement, or embrace an established movement. Whatever you do, don't just sit there.