Just for your records, 'neither' means NOT both, and 'either' means the opposite. I think you were looking for 'either' in both this and the last comic.
Actually, nope. I made it with GIMP. :D
My method is that I first write the text, as a separate layer. When that is done, I pick a brush that has blurred edges and make the basic color white. Then I just draw that bubble on the BG-layer (not the text layer, as the text disappears if I do that! :D) and then just anchor the text layer to the BG-layer. Simple, yet efficient trick. ;)