We all know what Siri can do. Whether she’s found a place in our daily routine is another issue altogether, but it’s pretty clear that Apple’s humble personal assistant is unlike any other voice recognition app.

But Siri’s real expertise lies not in her encyclopedic knowledge or weather forecasting; what makes the technology so amazing and useful is its ability to actually understand what we’re saying--so much so that the iPhone’s speech recognition is just as useful useful when Siri isn’t summoned. (Though it might not be as much fun to show your friends.)

Anytime the keyboard comes up, iPhone 4S users will notice a tiny microphone icon to the left of the space bar. Selecting it brings up Siri’s familiar interface, with one exception: Siri’s on a coffee break. Instead, Apple’s Nuance-licensed dictation is turned on, and the words you say are instantly converted into text (once you tap “Done” on your phone, anyway). Of course, you’ll need to interact with your iPhone’s touchscreen a little more than you would with Siri at your side, but you’ll also be able to get more done.

Apple Apps

Dictation works remarkably well with all of Apple’s iPhone apps, but it really shines in Mail, Notes. Pages and anywhere else the predictive keyboard--no matter how much better it’s gotten--still stands in the way of progress. Dictation’s great for taking notes and writing lengthy e-mails--especially if you want to save a draft or back up to iCloud, two of Siri’s notable shortcomings. (However accurate dictation is, though, it helps to have a pretty good idea of what you want to say; your phone will try to interpret your “ums” and “uhs” as actual words, so you’ll have to do a fair amount of editing.) It’s not perfect by any means (see below), but Apple just might have eliminated one more roadblock on the path to a post-PC world.

Dictation is also quite helpful in Messages (but Siri is the better option here) and Reminders, but not so much in iCal and Maps. Our mileage varied using Safari (for example, we still had to press the “Search” button), but we did notice that Apple turned off the feature for all password fields--an obvious security measure, and we definitely could see a special Siri login feature built into Safari down the line.

Third-Party Apps

iOS 5 and the iPhone 4S are both fairly new, so the landscape isn’t exactly teeming with  dictation-ready apps, but Apple’s been kind enough to build its little microphone button into the OS-wide keyboard. Since Apple has already done the heavy lifting, speech-to-text will work in any text field, but depending on the app and how the text is being inputted, dictation might not actually save you any time. If you have a favorite text editor or list manager, dictation will be a godsend, but search fields will be fairly useless. We tried using it with the word-heavy Sporcle app, but the game refused to recognize words that weren’t typed.

However, since Nuance’s speech recognition is so accurate, there are myriad options for developers to work dictation into their apps once a proper API is made available--such as Target’s own Nuance-licensed “Speak to Search” feature that automatically scans available products upon hearing a request, and iTeleport, which leveraged dictation to send text to a remote computer. And we’d bet that Twitter and Facebook--along with a slew of others--will be marrying their apps with dictation automation soon enough.

And Beyond

Since Apple wasn’t even satisfied enough to take her out of beta mode, it’s clear that great things are planned for Siri. When you think about it, Siri is more than just another killer app for the iPhone 4S, it’s a whole new input interface. We already see it in action with composing emails and getting directions with Siri, but speech could take over complicated gestures on the iPhone, iPad and, yes, even the Mac. There are already rumors about Siri replacing the remote on the fabled Apple TV set and it’s entirely believable (assuming you believe the TV rumor in the first place). We’re certain to see Siri make its way to the Mac sometime next year, and as Apple perfects the speech-to-text technology, we expect to be talking a whole lot more to our computers and doing a whole lot less double-clicking.

Read on to see Siri used as a dictation device.