Bioware discusses the thought behind their map creation.

Recently BioWare released a developer blog that focuses on how maps are generated for the upcoming Star Wars: The Old Republic. Through the use of metrics and analytical software the developer discovered that the single most used UI function was the map. With careful consideration they decided to make the map as useful, friendly, and accurate as possible.

The worlds in The Old Republic can range in size up to six times that of what might be considered a "standard zone" in modern MMOs. A player will only be questing or utilizing small portions of a world at any time so it was deemed that multiple maps were needed for each world.

This brought up the question of how to break each zone down into smaller maps while maintaining usefulness. BioWare came up with a solution for this concern and added extra features like quest helpers for both the player and their group mates. This write up truly shows that BioWare is thoroughly examining every aspect of SW:TOR.