Advance Wars - Duel Strike was the first Advance Wars title to come out for Nintendo's new DS console. The series's turn-based warfare was very popular on the Gameboy Advance, and Nintendo stuck to it's guns with this version. There are little to no changes in this version compared to the Gameboy Advance versions. The graphic sprites are the same (or slightly different, as I didn't really compare the two side by side) and the gameplay is nearly identical. There are slight differences though, like the DS's ability to use the stylus to move your units and create maps. This was a very impressive game back when it first game out, but since then a new sequel to the series has come out. It would be worth your investment to track that version down and not this, especially if you are familiar with the Advance version.
Overall, solid but nothing new.