All you do is tap the little Record button, then start talking. Tap again when you're done and the app quickly returns your translated text. Another tap and that text becomes an e-mail, a text message, or the contents of your iPhone's clipboard.
It really is that simple. Here's a short video that shows Dragon Dictation in action:
What the video didn't show was that if the app makes a mistake, you can tap the misrecognized word to bring up a list of suggestions. There's also an onscreen keyboard you can use for more detailed editing.
Amazingly, Dragon Dictation requires only 1MB of space on your iPhone. That's because it works its magic via the Internet, much like the music-recognition app Shazam. The only downside is that you can't use it offline, like when you're on a plane.
Equally amazing: Dragon Dictation is free, at least for now.
One thing that bugs me about the app is that there's no "start over" option. If you want a clean slate of text, you either have to manually delete what's there or exit and restart the app.
Also, it's worth noting that the app uploads names (and only names) from your iPhone address book to Nuance's servers, ostensibly to improve name-recognition accuracy. I don't have a problem with that, but I can see where it would represent a security concern for some users.
This is really an incredible little app, one I think any iPhone user will be glad to have on hand.