I have spent about a week using DD4 around my home office. I noticed right off the bat that it is faster than version 3.5, and control of other applications like Apple Mail and Safari are smoother. Version 4 has also added precise control of Gmail, making creating, editing and sending a message a completely hands-off affair. Apple's Pages is also directly supported, so you can do all your formatting of text and speak other commands that would otherwise require mouse moves to a menu. It should be noted, however, that Pages 5.1 reduced support for AppleScript, so you don't get quite the range of options that you did with earlier versions. Big mistake, Apple.
As a test of transcription, I downloaded a couple of podcasts. You point the Dragon application to an audio file, and it starts taking in sounds to turn into text. You then highlight a sentence of the converted sound file and make any corrections to the text. If needed, it's possible to play the audio file to hear what actually was said. Dragon needs about 60 seconds of corrected text to create a conversion profile, after which you play the sound file and the transcript appears in faster than real time on your screen. I played a 15 minute sound file into Dragon Dictate and it had the transcript ready in about 5 minutes. Things are surprisingly accurate -- better than 99% in my tests -- but one issue is there are no automatic paragraph breaks, which makes for a pretty large chunk of text to navigate. I have suggested to the Nuance folks that the app should automatically insert paragraphs based on pauses in speech, counting sentences, or every 20 seconds or so.
Transcription is a great feature for students who want to preserve a lecture, or anyone wanting to turn recorded speech into editable text. The microphone needs to be pretty close to the speaker though, as you won't capture usable audio at a distance. Supported audio files include .mp3, .aif, .aiff, .wav, .mp4, .m4a, and .m4v.
One nice way to record audio is to use the voice memo app that comes with iOS. When the recording is complete, email the file to yourself and let DD4 transcribe it. I tried that with a 40 second file and the transcription was perfect.
Are all transcriptions mistake-free without editing? No, but Dragon Dictate 4 sure beats hours of typing. You will usually have to make some corrections.
Of course Apple has long been involved in text-to-speech, and Mavericks has a built-in dictation function. It does need an internet connection, but you can download a large file that will allow local processing of speech just like Dragon does. Although neither company admits it, it's likely that Siri and Apple's OS X dictation are really Nuance products. Apple dictation is not nearly as powerful as the Dragon Dictate product, but it works well for basic dictation.
If you want to dictate to your Mac while also controlling various apps without ever picking up a mouse, Dragon Dictate is the app for you. There is a certain joy and freedom that comes with seeing your words accurately appear on screen. I also love using Safari with voice only, initiating Google searches, clicking on links by voice only, and scrolling pages up and down.
Dragon Dictate 4 requires an Intel Core Duo CPU running at 2.4 Ghz or faster. The app currently supports both OS X Mountain Lion and Mavericks. A headset/microphone is included with purchase, but I did fine training the app with my Blue desk microphone. On my Mac laptop, I did quite well using the built-in microphone. By the way, this review was mostly written using Dragon Dictate 4 by dictating directly into our content editor on Safari. Making hyperlinks still involves using a mouse for part of the work.
Dragon Dictate 4 sells for US$199.00. An upgrade from version 3 or 3.5 is $99.00 during this month. After that upgrade pricing for previous owners with a valid install of Dragon Dictate or MacSpeech Scribe is $149.00. Dragon Dictate 4 can be bought directly from Nuance or resellers.