Well in 6 years, WotC has offered up nearly 3 editions of it's role playing game. This third version (and 5th over all after the first two West End Games version) is probably the best mechanically they've put out.
What's out: it is no longer Dungeons and Dragons set in Star Wars. Skill point system is entirely gone. Wound Points. The Force as a skill set draining vitality.
What's in: Simpler skill mechanics, just name the skill, it's yours. The classes seem to be a bit more inclusive. Talent trees are introduced which open up the massive amount of abilities and powers we see the heroes use in the films.
What's not good: The book claims to be the complete definitive all inclusive resource for all eras. That is a flat out lie. The examples of movie and EU characters maybe from all over, but it doesn't provide how all the characters mentioned would use a given skill or talent. Also, when it lists planets it is the same tired old list of Coruscant, Corellia, Bothuwi, Alderaan, Yavin, Endor, etc. The ship chapter leaves out just about everything prequal. The characters only give blocks for one character in either RotJ form or RotS form. It doesn't show the progression or change. From a mechanic perspective, the defense ability is a bit confusing now.
What hasn't changed: Droid rules. Most feats. Ability scores. The basics of d20. Creatures are the same relative to heroic characters as before.
Recommendation: If you thought previous editions of the RPG were too confusing, this would be a good pick up. This edition lacks the background and reference material of previous editions. The Force is probably what it should be for a decent RPG because no one system is going all inclusive. Because of WotC failures or lack of effort in previous editions, this looks stellar, but that means for a passing grade of a C they lowered our expecations.
The good news is that from CIV there will be a Starships of the Galaxy coming soon. Also, there should be updates how to incorporate older source books into the game on the website over the next year and at fan site.