I don't know what happened to this game... but somewhere along the way, almost everyone I know (and that's everyone I know, but I'm leaving room for possibility) seems to get this game wrong. When I was growing up, it went something like this: One person asks another "Truth or Dare", and the other person responds with their choice-of-the-moment. At that point though, they're comitted... there's no going back. Sure, there might occasionally be the flexibility to swith back or forth, depending on how good/bad/scary/difficult presented option is to confirm or perform.
The problem here is, that's not how the game is supposed to be played! See, the real idea behind Truth or Dare is to get information, but let someone choose to pay a price for not answering. How can I possibly know which I want if I don't have any information about either?
The game's supposed to go like this: Person 1: "Truth or Dare... you and xxxxx did it?!", at which point person 2 can decide if they want to answer the question or not. I mean, if you have to pick Truth or Dare first, and you choose dare, how do you know you're not avoiding something as mundane as "Truth: your hair is brown" or "the sky is blue"? I know those would probably never come up... but you can't possibly opt out of answering a question if you don't know what the question is yet.
Some might argue that it's really about risk and ultimately, taking a gamble... but I don't think so... it's about secrets. It's about opening yourself up to being asked questions you wouldn't normally allow to be asked, while still having an out if you don't want to ask it... and also accepting that the price of keeping a secret might be more than it's worth... but once you've made your choice, you're stuck with it.
...as I type that, I realize that even then, it's not really about secrets, but about the importance of truth. It's a kid's game for demonstrating that the price of keeping a secret can be very, very high. I mean, if you have no secrets, then you'll always say "Truth"... and while you're friends may think you're lame for doing so, the price you have to pay (in the form of a dangerous or embarrassing dare) is always zero. Plus, I don't think there's anything in the commonly-accepted rules that says the same question can't be asked twice... which means the price could go on and on and on. The game reinforces the idea that it's usually easier to tell the truth, and accept those consequences, than to keep a lie and pay even more dearly for it.
...but the main point is that most of us play the game wrong. There are a lot of things that you might think are secrets or embarrassing for me... and I'd like the option of opting out of them, but only after I know it's worth taking a risk for.