OK, I think it's a given by now that developing for the Nintendo DS is hard. That being said, game publishers can no longer ignore the massive success of the handheld now having shipped more than 50 million units.
The good news is that titles like Call of Duty 4: Modern Warfare are coming to the console. The bad news is that tiles like Call of Duty 4: Modern Warfare are coming to the console.
On the surface, the availability of a title like CoD4 on the DS is really good news. Having played Call of Duty 2 and 3, I can attest that they are really great, if not very long, games. The problem is fitting that franchise on the DS. The title only comes with one control scheme, this control scheme was pretty much the one used in Metroid Prime Hunters and it didn't work in that title and it doesn't work here either. In fact, the harshest criticism I had about Metroid DS was how hard it was on the hands to play that title, I gave up on it only after a few plays.
The problem with CoD 4 on the DS is that it's clear that the traditional control scheme of the franchise, found on the XBox 360 version of the game for example, is a much better fit. Unfortunately, Activision decided that one control scheme was enough and didn't include an option for it.
I'm all for innovating but more often than not it seems that the price for innovation on the DS is bad controls. Call of Duty 4 on the DS is nonetheless a game with high production values, even delivering speech for all the text in the game, however, it's also clear that the control scheme just doesn't work. Finally, the most frustrating thing about the experience is the DS has all the buttons and controls necessary to actually enable the traditional control scheme.