Shorthand Version: The game still rocks
Long Version Follows: It amazes me how a turn based game like Advance Wars can last so long without restructuring its game mechanics and still kick ass doing it. Even with Pokemon the combat started to feel stale to me but AW just seems to get better.
Most you who have played or read other reviews know the jist of why this games awesome but im going to add a bit more pertaining to what ive experienced.
1: Anti-Tank Units are the Devil! Such a great and frustrating addition to the game, the Anti-Tank is that trump card that can easily make a defense or break your attack. If you don't know, the unit allows you to do great damage to land units and Helicopters. And the best/worst thing about them is that despite having the indirect fire ability the Anti-Tank can return fire on a direct unit attacking it. So think of it as Artillery that can attack direct as well.
2: The AI is Napolean worthy I haven't got too far into the story, mainly because the training missions are so time consuming. Granted the story missions are easy but the training missions you unlock along the way are no cake walk. Going into these missions expecting to rush the enemy and win will lead you to a quick defeat. Is this a bad thing? Of course not. It makes the victory all the more delicioius. Your enemy always seems to know what you plan on building and what your next move is. Maybe it is just me but I have noticed a great improvement on the AI.
3: Mayors are Fat and Greedy The story is really enjoyable so far. Not that I had a problem before with Andy and his friends going into a battle with smiles and just beating up on the bad guy but this already has more substance and im only on mission 10. For example the town you come across with the lone survivors. They don't want military with them since they don't want to feel opressed(spelling?) but they won't hesitate to cry for your help to save them from bandits, only to shun you and your crew again once you're done saving them.
More comments to come along the way, unfortunately working full time and 3 hour classes at night have prevented me from getting as far as I would like to. But like I said before if you have a DS then don't hesitate to pick this one up.