Amazon.co.uk Review
In a nutshell:
The greatest strategy game in portable history maneuvers onto the DS with new units, new COs (commanding officers), new game modes and the most addictive gameplay this side of
Tetris. It may not have much in the looks department but in gameplay terms this is the supermodel of turn-based combat.
The lowdown:
Mixing chess-like complexities with an anime plotline, Advance Wars is one of gamings most unlikely heroes. This marks the most significant overhaul of the series yet with six new units and dozens of new features, including a real-time mode. The stylus control and dual screen display are really just gimmicks though, and its the new dual strike attacks that are the most interesting idea, with COs double teaming for some battle turning super moves. COs can also gain "experience", as in a role-playing game, allowing you to fine tune your armys abilities like never before.
Most exciting moment:
A tense four way battle against friends that ends in a double whammy duel strike from hell.
Since you ask:
The Advance Wars series has been going since 1988 in Japan, where its known as Famicom Wars. The first to make it to the UK was Advance Wars 1 on the GBA in 2002. Advanced or not, war has historically been viewed as a bad thing.
The bottom line:
The best DS game yet and probably the best Advance Wars ever. 
Harrison Dent
Manufacturer's Description
On the heels of its last defeat, the nefarious Black Hole Army has fallen under the control of a deadly new commanding officer. He has sent its new COs to attack the nations of Wars World once again, and it's up to the allied armies of Orange Star, Blue Moon, Yellow Comet and Green Earth to put an end to Black Hole once and for all.
Advance Wars: Dual Strike uses both screens: the touch screen for battles and the top screen for special information, from unit and terrain details to special conditions in each battle. In special DS Battles, players fight on the top screen as well, commanding both battles and redeploying units from one screen to the other. The Map Editor now uses the stylus, so that players can draw their maps right on the touch screen. Players now can trade their maps wirelessly too. Players also can use the stylus to give orders to their units; from moving to attacking, they control everything from the touch screen. Each time Commanding Officers win a battle, they gain experience--over time, they can learn new battle skills that increase their strengths or boost a unit's abilities. There are more than 40 battle skills. Each of the COs has two separate special powers: a CO Power and a Super CO Power. These powers can freeze the battlefield, boost the attack range, rain bombs on enemies and much more. Now COs can team up for Dual Strike attacks with even more impressive results. New playable units include hulking aircraft carriers, invisible stealth fighters, devastating omni-missiles and insanely powerful megatanks.
Key features
Use the top screen for quick-reference battle intel, or take control in battles that rage across both screens. Command a fleet of fighters high in the skies while troops clash with the enemy on the ground far below. New COs, new Tag-Team battles: Choose from new Commanding Officers, and combine their powers for incredible attacks that can turn the tide of battles. Real-time Combat mode: For a battle with a twist, players lead soldiers into a fast-paced, action-oriented battle against a storm of enemies. Easy-to-use map editor: Just grab a stylus and draw maps right on the touch screen, then send the maps to friends wirelessly. In Campaign mode, players fight back against the Black Hole Army's invasion. Vs. Mode offers dozens of new battle maps, as well as tons of favourite maps from the previous two Advance Wars games. Players can play both normal and DS battles, both single and multiplayer, providing endless replay potential. Combat mode gives players fast-paced action: Instead of turn-based battles with large armies, players fight in real time while controlling a single unit. Both Combat and Free Battle are available for multiplayer matches. Using DS Download Play, combat can be played wirelessly by up to eight people using a single game card.