Thank fucking God. I loathe version names. Place these in release date order: Lion, Snow Leopard, and Tiger. Now, place these in release order: 10.6, 10.7, and 10.8. Which do you find communicated more useful information?
Dude, version name is a great vessel for branding and promotion. Most distros have version names and version numbers, it's not hard to dereference a version name and they serve a purpose.
More brand awareness for open source projects == good.
Historically the name came first. Engineering would start working
on a new version, Foo, and later on Marketing would decide it if was
going to be 1.3 or 2.0
At least that's how it worked in commercial software. Now the names
have taken on a life of their own.