MUST WATCH PRIOR TO EPISODE 3.
A little (way) over the top, and I'm not sure if it is canon anymore (or if it ever was) now with the introduction of the Clone Wars animated series (that I haven't seen at this point).
It's quite good however - from an animation and cinematography point of view. Much more interesting and enjoyable than the clusterfuck prequel movies themselves and quite possibly my favorite piece of Star Wars fiction so far.
Loved it. All of the characters are 100 times more badass. Even the clones have achieved maximum asskickery.