This game has just been released (in Europe, soon US) and it's very good in my opinion. A good mix of RPG, turn based strategy, a little city building and resource management. The AI is good, not genius, but fortunately the game throws lots of battles at you which is the fun part. There are heaps of characters you can recruit into your armies, and lots of options.
The game web site is at http://www.koei.com/rtkxipc/ if you want to have a look.