After renting this game for 5 days from my local video store, I have to say I'm impressed.
This game is detailed, addicting, time consuming, enthrolling and exciting -- just like every RPG should be.
For the non-star wars fans, I would suggest it. For Fans, I would highly recommend it. I would even go so far as saying this is probably the funnest game a Star Wars fan had ever played.
The story starts off after a war, and all the Jedi's are eliminated, save one. That one is you, and you go through the story deciding whether or not to become good or evil. The choices are mainly made through conversation and interactions with others. When someone talks to you, It'll give you a list of 3-6 responses, and how you respond will determine how evil you are.
Just like any great RPG, you become greater and greater as time goes on. You gain experience from figuring out puzzles, killing monsters, disarming traps, etc, etc, etc. Experience points lead to levels, which leads to enhanced abilities (and there's a huge variety) and increased attributes.
There is also a wide variety of items, and your abilities determine how you use them (and how effective you are at it)...
Possibly the best part of KOTOR is the story. Peice by Piece it introduces it through story telling of other characters, cutscenes, and through playing the game itself. Very fun -- especially for Star Wars fans.
I recommend this game to almost anyone. You'll love it.