Yay or nay: Hand-held video game players?

Hot topic among parents of 5-9-year-olds, especially in the post gift-receiving season: To DS or not to DS?

For those of you lucky enough not to know, a DS is a Nintendo DS, a hand-held video game playing device. (Another contender is the PSP--PlayStation Personal.) The kids love them. Like, love. Lo-o-ove. And plenty of the kids have them.

Mine doesn't, and I'm wondering how long I can hold the line, and even if I should hold the line. (Let's pretend that the cost doesn't matter. It could be a birthday present from a kindly relative with more disposable income than I have.)

Now, clearly I'm pro-video game. I work for a video game company; we have a Wii; my kids play games online. But I also see gaming as a communal, interactive activity: The company I work for makes multi-player games (so kids play together). I don't put a time limit on Wii play at my house. Instead I let them play while they can cooperate and have fun together; when the fighting starts the game is over. And they're only allowed to play online if they can figure out a way to either play together or cooperate.

The hand-helds just seem isolating to me. A kid is playing alone, immersed in a game with no interaction either within the game or outside of the game. And that kind of weirds me out.

On the other hand, is that just because I'm an extrovert? Is isolation that bad? And what about the times when I wish my kid would isolate himself, like on the looooong subway ride down to school every morning? There are only so many games of "let's count and skip the multiples of 4" that we can play before he gets bored and the kids start punching each other. We're learning the two-letter postal abbreviations for the US states now. Next we'll do the military letters (alpha, bravo, charlie, etc.). After that we'll move on to what? Maybe airport three-letter codes.

Maybe a hand-held would help with that long ride and preventing fights from boredom.

Is that reason enough to get one?

What do you think? Does your kid have one? Are you for or against in theory? In practice? Are there aspects I'm missing?