The latter. According to the article the 'like neurons' part just means that they use ion channels to communicate. You could argue that the title of the article is slightly misleading, but then again this is an article that talks about 'charged ions'.
"[...] ion channels conduct long-range electrical signals within bacterial biofilm communities through spatially propagating waves of potassium. These waves result from a positive feedback loop, in which a metabolic trigger induces release of intracellular potassium, which in turn depolarizes neighbouring cells. Propagating through the biofilm, this wave of depolarization coordinates metabolic states among cells in the interior and periphery of the biofilm."
From the abstract of the paper (http://www.nature.com/nature/journal/vaop/ncurrent/full/natu...)
"[...] ion channels conduct long-range electrical signals within bacterial biofilm communities through spatially propagating waves of potassium. These waves result from a positive feedback loop, in which a metabolic trigger induces release of intracellular potassium, which in turn depolarizes neighbouring cells. Propagating through the biofilm, this wave of depolarization coordinates metabolic states among cells in the interior and periphery of the biofilm."