The Dragon apps are nearly a year old, but have only just been released in Australia, with support for recognising Australian accents. They're dead simple to operate; in the dictation app, hit the record button, say what you want to say, and hit Done to have it processed. The same happens in the Search app, save that your query is instantly sent off for searching. (Of course, that latter option has long been possible on iPhones with Google's Mobile app.)
The accuracy rate was not particularly stunning in my tests. I know that I speak quickly and that this poses a challenge for most voice recognition services, but even when I deliberately slowed myself down, words often got passed over or mangled beyond recognition.
The screenshot shows what happened when I spoke the opening words to ABBA's "Dancing Queen" as normal sentences. It's representative of the best-case results I got across a bunch of test text. The search application worked somewhat better, likely because the ability to identify common search terms and the use of shorter phrases meant there was less to handle.
Both Dragon apps are for iOS devices, and are currently free (though developer Nuance says this will only be for a limited time; if they do start charging, I'd presume the on-screen advertising for other Dragon products would disappear).