Advance Wars: DoR is definitely the big one for me. Field Commander was a lame and ineffective patch to get my AW fix, but DoR is most likely going to be awesome and deliver ridiculous amounts of playtime. By the way, DoR is 4th in the Advance Wars series, too...
On the DS front, there's also Warhammer 40k and Panzer Tactics DS, though I might not have much need for them after DoR. Basically also Rocket Slime and Phoenix Wright but I wonder if I'll ever get to them. There's also Warioware: Twisted! which I've been wanting to get for a really, really long time but have somehow always passed on...
I've also been hearing very good things about that And Then There Were None game, it's definitely made a big jump in my list of interesting games. I've also been wanting to get my hands on Raving Rabbids 2, now that the insane end of year flood is cooling down. Also Nitrobike, Sonic & Mario (& Miis) and later in the year, Dragon Quest Swords.
Oh, and I'm not paying Xbox 360 prices for games, they're just ridiculous. It's one of the reasons I'm not getting the box.