Now that I finished story mode in 7.5 hours (give or take) it's time for my final review. Part of that was time spent holocron hunting or pausing the game, so it's probably closer to 6 and some change. The story mode feels really, really rushed. My two main complaints are the lack of diversity in the mobs and not enough story. It's not really until the last chapter where there's anything resembling dialogue outside of a cut-scene.
I tried the first challenge, which is designed to teach you all of the various lightsaber combos but with a twist. You have to do all of them, as dictated to you, within a time limit. And you have to nail the timing perfectly. After failing this one, I looked at the descriptions of the other challenges. Run across this terrain in this amount of time, defeat these stormtroopers before they can escape, etc etc. If this appeals to you, the game has quite a bit to offer after the story mode is finished. Most of them unlock as the game progresses and I think others unlock as challenges are completed.
The good:
The action is fun. Aside from throwing the same things at me nearly every fight, it was still fun to slaughter countless stormtroopers, scouts, and TIE fighters.
The force powers are balanced and slightly improved. The addition of the mind trick is brilliant.
The graphics are a huge step up from TFU 1.
The bad:
Short. And to top it off, replay value is limited.
The diversity of enemies is lacking. It degraded into variations of the same 6 things over and over and over. Some of these were fun, others quite tedious.
Lots of platforming over ridiculously precipitous chasms. In some cases, if you fall you're just brought back to a checkpoint without interuption in game play. In others, well, yes, you do die.
Severe shortage of dialogue. I realize they needed to change the tone and setting from the first game, but it felt rushed and forced. Some more character interaction is greatly needed.
Final score: 6.0 out of 10
It wasn't a horrible experience, on the contrary it was actually quite entertaining. However, it does lose a lot of points due to shortness, a rough story, limited replay value, and unimaginative enemy and level design. I also knocked off a point for some items I felt were missing in the UI (mini-map, combo bonuses, name of enemy killed). Overall, it's worth playing but I highly suggest either renting or borrowing this game.