The slogan, "at the sign of the dot bomb" is used in the current logo because the letter "o" in com is replaced by a cartoon acme bomb. The slogan only makes sense if a bomb is used somewhere in the logo. Entry #12 uses it effectively but all other entries that use it don't have any bomb reference. So if there is no bomb then there should be no "at the sign of" strapline. Apologies if I that was not clear from the initial brief. As I said in the brief I am happy to see designs without bomb and strapline but its all or nothing. If you want to use the strapline you need a bomb. No bomb no strapline.
Having seen a number of designs without the .com I've decided that the winning logo will include .com and that I am likely to favour .com in a smaller font than WarGameStore, entry #5 is a good example of this.