Blag Hag has put up a poll for the most influential Atheist of 2009. Ariane Sherine is on the list and I suspect for most UK atheists she will be the natural choice. Her Atheist Bus Campaign touched a nerve and rapidly drew enormous support. As a result atheism, humanism and secularism have become respectable mainstream life choices and more and more people are willing, even eager, to speak out against the dead influence of superstitious, archaic belief on our lives.
Blag Hag provides a list of 16 nominees with short biographies and a place 'Other' for suggestions. It names some atheists that I hadn't previously heard of but I look forward to getting to learn more about them soon.
Good luck to them all.