9-5Mac has a good demo of the new Dragon Dictation for iPhone a free app for the iPhone that seems to have good results for voice recognition.
This is sadly, only available in the US store. However, it's fairly easy to create yourself a new account:
Logout of your account in iTunes
Switch to the US iTunes store (or whatever country you want to create the account in)
Download a free app
When prompted, create a new account
Put in a new email address (ie: email@example.com), use a valid US address (this one is a good choice) and your other information. Note that you aren't asked for a credit card (because you're downloading a free app you see) or valid mailing address associated with that credit card.
Do whatever confirmation dance is required to confirm your account
Download your US only content
When you want to switch back to your "real", non-US account just logout and log back in with your normal account login.
The only thing to keep in mind here is that sometimes when checking for updates to apps sometimes you'll get notification that there is an app with an update, but when you click 'view updates' there aren't any. If this is the case, it's probably a non-local app has gotten notification of an update, but your check in the local iTunes store doesn't find any. Just log into your other iTunes account and hit the 'check for updates' button again.