Here's in interesting
Q\A post I found on IGN's site with SWTOR's game director James Ohlen. I zeroed in on this and thought it would be worth sharing. Another opportunity to role play our characters a little bit. No matter the faction at that!
IGN: Can you explain what the Legacy system is meant to be?
James Ohlen: What we're giving at ship is basically just a taste of the Legacy System. It's allowing you to essentially choose your legacy name, essentially your family name. You're creating a family, and you can populate that family with children or siblings, but you can also populate it with friends and henchmen. Even though it's part of a family you can still have aliens or people that aren't actually related to your other characters. This is one of the features that we have a lot of people focused on right now. All the characters in that family tree are going to share the benefits that come from being part of that family and those benefits are going to include new powers, new items, there's going to be a whole bunch of different things that you're able to unlock through the Legacy system.
The inspiration for it is that Star Wars is very much about family, you have the relationship between Luke Skywalker and Darth Vader or Anakin Skywalker so that was what started it off. We also wanted another reason to reward players for playing more than one character. If you decide to be the player who plays the Bounty Hunter and an Imperial Agent and a Jedi Knight, you're actually rewarded for doing that because you know they can all be part of the same family tree.