When all of those iPhone 3.0 features were first announced, one of the features that stuck out most to me was the incoming A2DP ability -- the new iPhone OS will let you stream out music to a Bluetooth source, like headphones... or your car. And over at Cars.com, the guys got their hands on a Toyota Venza with Bluetooth capability, and did just that, as you can see in the video above. It's pretty slick -- no wires, no annoying pairing, just hit the Bluetooth button on the iPod, choose the car's Bluetooth source, and press play. We're not sure about audio quality (it should be at least listenable), but it looks super cool.

There are, as usual, some catches. I for one was disappointed to hear that this A2DP ability won't work with first-gen iPhones like mine -- you'll need to have a 3G to do something like this. And of course, this will require the iPhone OS 3.0, which isn't technically out yet (though devs in Apple's development program are playing with it right now, which is why you can see it in the video above). And finally, you'll need a car with the Bluetooth capability, which (though I haven't owned or shopped for a car for a few years, so maybe things have changed a bit) is still kind of hard to find.

But hey, even if you're not there yet, here's a look at the future. Where we're going, you won't need wires to get your iPod playing music on the car stereo.

If you've been listening to all the clamoring on Twitter, or perhaps have seen the updated Apple page, then you know there was an iPhone event today to discuss a new version of the iPhone OS, version 3.0. While you will have to wait until the summer to get the new version (unless you join the developer program), Apple showed off over 100 new features that we're all excited about. iPhone developers are also getting some love from Apple with over 1,000 new APIs.

Some of the biggest updates include:

• Push notifications will be standard in iPhone 3.0. Apple claims that there was a scaling issue when they first announced this feature last year, with thousands of developers clamoring to use it, so it had to be delayed. Developers will be able to build message, sound, and badge alerts into their applications.
• iPhone will support cut, copy and paste -- copy text and pictures, then paste them in any application on the device. If you change your mind about the newly pasted data, just shake to display a menu asking if you wish to undo the paste.
  
• In-App purchasing -- developers will have the ability to charge a fee from within the application for more levels in a game, magazine subscriptions, eBooks, etc. This solves the problem of the 20 ebook readers that only allow you to read one book each.
  
• MMS -- you'll be able to use MMS on your iPhone 3G (yes, 1st gen iPhones will not get the fortune of using MMS due to the use of a different cell radio). The new Messages application will be taking the place of the SMS app and will allow you to send voice memos and pictures to your friends.
  
• Peer-to-Peer connectivity -- allows iPhone apps the ability to find other iPhone users over WiFi or Bluetooth. This can be using for anything from gaming to sharing data.
  
• Third-party Accessories -- app developers can now access third-party accessories attached to the iPhone. This could allow for developers to interface with their own accessories to create a truly unique experience on the device. One of the demonstrated uses was a prototype blood glucose meter for the iPhone, from a Johnson & Johnson subsidiary, which is already getting attention from our readers; it's not for sale yet!
  
• Apple will now be allowing applications the ability to get GPS coordinates from Core Location and turn that into software that provides Turn-by-Turn directions for iPhone users. However, due to the terms of use with Google maps, developers will be required to license their own maps for this use (meaning that Turn-by-Turn GPS applications will almost certainly be paid apps). This isn't a problem for vendors like TomTom or Telenav, who already have licenses for their map data.
• A landscape keyboard option is now available in all iPhone applications, including the infamous Mail.app.
• Voice memos will allow iPhone users the ability to capture audio and then email it, or send it through the Messages application as a multimedia message.
• System-wide Spotlight searching is built right into the home screen. To the left of the first home screen, there is a magnifying glass, so by flicking to the left of the first home screen will show this search app. You can search for anything, including mail, music, and notes. There is no word yet on how this will interface with third-party applications.
  
• Stereo Bluetooth audio devices are now supported through the use of A2DP technology.

iPhone owners should note that A2DP technology and the use of MMS will not be available on 1st generation iPhones. This is probably due to the iPhone Bluetooth spec used, and Apple has confirmed (during the Q&A session after the keynote) that MMS is not available because of the cell radio used.

iPhone OS 3.0 will be available for regular users "this summer." iPhone developers will be able to get the beta of OS 3.0 sometime today -- Apple is still busy updating their iPhone Dev Center, but we'll let you know when it is available.

I've always found it surprising that Apple did not have support for the A2DP Bluetooth audio profile in Tiger. A2DP is the profile for stereo music, as opposed to the lower quality mono profile for standard phone headsets. It was rumored, but not confirmed by Apple, that Leopard would fill this hole, and now it appears that's exactly what has happened. Ryan at Thoughts Abound has successfully set up Leopard with his Motorola S805 Bluetooth stereo headset to stream music wirelessly from iTunes. Not only that, he notes that "AVRCP is included as well so you can control your music from the controls on your headphones or stereo."

Unfortunately, A2DP compresses the audio, so it's not exactly a high-fidelity solution. But if you really want to listen to your tunes from your Mac without wires, this is probably the way to go.

As I understand it, there are a lot of new DAPs and music-enabled mobile phones that support A2DP - a technology that allows devices to transmit stereo audio to Bluetooth headphones. It's all the rage with the kids these days, and many fans of cutting cables wherever possible were a bit disappointed when the A2DP acronym didn't make the iPhone's feature list. Thanks to a tip from TUAW reader Earle Davies though, the iPhone apparently does seem to support sending any audio - including music and the audio tracks from your videos - to a Bluetooth headset that isn't even enabled with A2DP - but it aint pretty.

To tinker with this, you of course need to have a Bluetooth headset paired with your iPhone. I personally have an older HS-850, one of the first Motorola models with a microphone that flipped open to toggle the headset on and off. After you've switched your headset on and it's shaken hands with your iPhone, go into the Visual Voicemail screen and tap the Audio button in the upper right (which is otherwise a Speaker button when your headset isn't on and communicating with your phone). You'll receive an audio selection dialog much like the in-call dialog that allows you to chose where to send the iPhone's audio. As you might guess, select the Headset option, then switch over to the iPod and begin playing music or a video. This, unfortunately, is why I had to include 'kinda' in this post's headline - while the iPhone sends audio to both Earle's Motorola H700 headset and my HS-850, it still plays audio though the iPhone's speakers as well. It's a bizarre quirk I can't seem to figure out how to stop, which makes me think this is either an unfinished feature or, perhaps more likely, simply a side effect of some of the iPhone's functionality.

Whether you can use this trick to get the iPhone to send stereo audio to a true set of Bluetooth headphones I couldn't tell you, because I own no such headphones. If you readers tinker with this more and help uncover more of what's going on here, please sound off in the comments.