Bioware posted a new article on the Star Wars: The Old Republic official site to introduce the new features being added into the game. The game brings a new dimension to the MMO experience by putting story front and center.
The details are as below:

"BioWare's vision is to deliver the best story-driven games in the world."
BioWare mission statement
"To create games that inspire, challenge and engage players."
LucasArts philosophy
Creating great stories in video games is a hallmark for both BioWare and LucasArts. Star Wars: The Old Republic marks the beginning of a joint effort between these two companies to bring epic storytelling into a massively multiplayer online game. We believe that there are four pillars of the roleplaying experience: progression, exploration, combat, and story. Achieving a high degree of quality in each of these will create a rich, challenging, and emotional gameplay experience. Among massively-multiplayer online games, story hasn't always received the same level of attention given to the other pillars. Star Wars: The Old Republic brings a new dimension to the MMO experience by putting story front and center.
What does this mean to you? When you play Star Wars: The Old Republic, you will experience a new level of immersion achieved through the following features:
- Epic Star Wars environments and story arc
- Class-specific storylines that evolve based on player choice
- Companion characters with individual motivations and personalities that will change based on player interactions
In Star Wars: The Old Republic you will have an emotional attachment to your character and face decisions in the game which will guide the development of your character and determine the direction of the character's storyline. Whatever your choices may be, you'll still be the hero (or villain) of an epic storyline which gives extra meaning to the other gameplay pillars. Character advancement will be much more than coming up with efficient statistics. Exploration will be about experiencing new places, new people, and new stories. Finally, instead of just reaching for that next level, you will be engaging in visceral combat reminiscent of the Star Wars movies where you're motivated to fight for more than just yourself - but also for a cause.
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