The Force didn't blow my mind, but there was some mild hemorrhaging.
What's good:
Graphics - Despite a few graphical mishaps, I think the game looks really good, especially considering this is the PS2 version.
Story - It's a great story line that throws some unexpected tie-ins to the original trilogy.
Difficulty - Well balanced to make sure you were challenged but never frustrated. The levels were a decent length with a generous number of check points along the way. They also have lots of those timed event things where you have to push the buttons in a specific sequence, but even those were fairly forgiving.
Unlockables - You can unlock new costumes, light-saber colours, light-saber hilts, and of course upgradable force powers. There's also lots of art work to collect along the way, if you're into that sort of thing.
Combat - It's fun! Okay, this is the big thing. I've mentioned below that the controls can be iffy, and the camera is clumsy, but not so much that I didn't still have fun. I had enough fun to forgive the game for it's errors, of which it does have. It's mindless linear fun, but if you just want to sit back and watch lightning consume the screen you may just have some fun yourself.
What could have been better:
Controls - They're not terrible, but I thought of some more intuitive ways they could have set up the force powers to be used. Some of the force powers were a little cumbersome to pull off at first. Not impossible, but they did require a learning curve that was longer than necessary. Also, sometimes you didn't exactly pull off the move you wanted to pull off. That is to say, you thought you were ready for the 4th and final move in an attack sequence, when in fact move #3 wasn't move #3 at all, but instead a block which interrupted the required string of button presses.
Lock on feature - It worked well enough for the boss battles, but during regular combat, it wasn't very effective.
Camera - You have full control over the camera, but it still needs some work. That is to say, it may swing around for you and get stuck behind something, or occasionally just decide not to point in the direction you really should be paying attention to.
Historical play - You can't go back and play previous levels! That would've been nice.
Some things just don't make sense - To be honest these things didn't really impact me at all. It's a game, and I was playing to have fun. I get why they had to toughen up the stormtroopers a little bit. However, some people may get perturbed when impaling someone clear through with your lightsaber doesn't always kill them.
It's short - again this is something that didn't bother me too much as I still had fun, BUT if you were hoping the number of hours it would take you to play through on your first run would hit double digits, you'll probably be disappointed.
It's linear - this is the last point that I need to mention that didn't bother me, but is worth mentioning as it can be a turn-off for some gamers. There's no secret areas (just secret turn-over-this-rock-or-box areas), no alternate paths along your mission routes, and even a few invisible walls. You have 1 road to take (but at least it's clearly defined). Again I was fine with this; I thought it fit in well with the whole loose-arcardey-fun-feel it had to it. One let down in this respect was that you can't go back and play through previous missions. You can only go forward, then repeat with force powers unlocked after you beat the game.
Final Word:
Easily a game which can disappoint if you go in expecting too much. If you like lots of game-play depth and open world environments, or if the slightest sense of cumbersome controls just ticks you off, you probably won't like this game.
If you like to occasionally sit back with your games, not think to hard, and watch pretty lights flash, then you may get a kick out of this one.
However, a good idea may be to rent it first. Once you finish it over the weekend (or maybe the same day if you've got 8 or 9 hours), you can decide if it was fun enough to buy.