AsterDW

My guess would've been that they did it to keep costs down, but they probably only saved $10.

I suspect you are partially correct, I believe it is a combination of weight and cost. Sure we think it only saves them $10, but multiply that by the number of consoles made and that can quickly add up to $30 million.

Asymetric gameplay options aside I have found the things noted by Leo to be good enhancements to the games. While having quick access to menus, items, equipment, or maps may not seem like a big deal it really becomes noticeable after you have actually used these functions and features. You don't notice how nice they are until you try and go back to playing the same game without those features. I don't think I could go back to playing Batman or Darksiders without the gamepad enhancements. They really do add to the general experience.

Beyond that the ability to play multiplayer games without split screen are very welcome improvement to how we played some games before. Even something as simple as Sonic and All Stars Racing with multiplayer having two of us with effectively full screen views at the same time were great.