I think a name can be helpful in pulling a map together in terms of the 'theme' sometimes. I know my first map suffered from lack of a consistent theme; after that I tried to focus each map more closely. Using a specific texture set helps the 'theming' of a map, too.
I have to say that the Unreal community sure as hell comes up with much more colorful and interesting names for their maps than the HL community. Then again, those Unreal maps are so purty they probably get all poetic thinking about them lol!
I started doing rough plans for a HL2 DM map this morning. I am planning on naming it Electrode, since the centerpiece will be a massive generator room. Sci-fi theme with lots of shiny metal. Assuming I ever have time to get any work done on it.