Samurai Warriors: State of War is basically the PSP sequel to Dynasty Warriors for the PSP, but set in Japan, with a little bit more fictional elements, and some improvements/deteriorates compared to Dynasty Warriors.
The game utilizes the entire screen, where Dynasty Warriors cut off the side. The fading of soldiers remains to keep the frame rate up and, as always, the fading is surprisingly never annoying. The graphics are as good as they were in Dynasty Warriors.
Also, there's finally some character dialogue, though in an Advance Wars fashion, where you have to read the characters' words to eachother back and forth, with little to no narrative.
Still no spoken dialogue, in or out of battle.
I never tried it, but they added in multiplayer, too. I think it'd only constitute as a multiplayer if all of the players fight in the same battle at the same time, which they probably do.
The only thing I didn't like about the game was that, though the combat gameplay still remained, was that the little board game section is much smaller than its Dynasty Warriors counter-part. There are less Generals, and because it's turn-based, the player can never be reinforced by allies in the middle of a battle.
The player gets less friendly soldiers than he would in Dynasty Warriors and, because of the turn-based board game style instead of live-action, the amount of the player's teammates never gets higher. The feeling of working in an army with allies is really lost in Samurai Warriors: State of War, making Dynasty Warriors, even with its smaller screen, a much more appealing game.