Who ever did the 'length' comparisons for that image is wrong. First it says the Enterprise is about the Length of the Chrysler Building which is only around 319m,
This is the problem in a nutshell. The length is wildly inconsistent.
Those are just code names used during production. The Enterprise was referred to as the Crysler Building, the Vengeance was called Trump Towers. It's part of their OCD security. You'll see in the Art of the Film book that Star Trek (2009) was referred to as "Corporate Headquarters" complete with faux logo (and in their size charts, the Kelvin was "Sweet Judy" and the Narada "Hansens Ranch", the shuttle hangar at the academy was "Tonto's Stage Coach Shop"), and in the concept art for Into Darkness, the film is referred to by the code name "Project HH"
EDIT: Ninja'd by everyone.