1. Liked it better than Reloaded, but not the original.
2. They tied minor plot points into the non-movie media. There are events and characters referred to that don't make a lot of sense if you haven't see The Animatrix or played Enter the Matrix. The Animatrix tie-ins I can accept, but the game ones I can't. Not everybody plays games and putting plot points (however minor) for the movies in the games is pretty weak.
3. Oh, so this is why the budget was so high.
4. Better exposition than in Reloaded.
5. If you watched the trailer released online at the end of September, they gave away too much (but not all of the) cool stuff again. Idiots.

It's well worth the money to see in the theater once, and then a bootleg DVD or internet download to go in and pick out little details - or nitpick if that's more your speed.