For quite a long time, atheism and secularism were understudied. Not anymore.
While Religioscope devoted a big article in French on this issue this year, a new review devoted to these topics just appeared in 2012: its name is Secularism and non religion.
Last but not least, let's remind the very interesting issue of the open access e-journal Approching religion (vol 2, n°1, 2012). Theme "The New Visibility of Atheism in Europe".