It seems as if we've been writing about USB 3.0 forever, but it has really been only about two years since Intel and other parties formed a promotional group for USB 3.0 in 2007. The spec was completed in November 2008, at which time the standard's backers said that a glut of devices would hit the market late this year. Well, that statement turned out to be almost right: Devices are coming very soon, but the glut won't be until next year.
SuperSpeed USB (as USB 3.0 is called) supports a maximum data rate of 4.8 gigabits per second, compared with 480 megabits per second for Hi-Speed USB (USB 2.0). That amounts to a theoretical maximum of 600 megabytes per second--it's way faster than most hard drives, and it's coming just in time for a wave of newer and speedier solid-state drives. To give you an idea of how fast that is, it's the equivalent of moving almost one full CD's worth of data in 1 second.
USB 3.0 achieves those speeds with a new plug and cable format, but it's all backward-compatible with USB 2.0 and USB 1.1. Plug in your old device, and it will still work (at the older speed). Plug a USB 3.0 device into a USB 2.0 port, and it will run at the slower speed.
What's more, the USB 3.0 protocol is now full-duplex: Devices can send and retrieve data simultaneously, which wasn't true with USB 1.1 and 2.0. Lower operating voltages and the elimination of broadcasting and polling (methods that the previous USB standards used to communicate with all attached devices) should make USB hosts draw less power, but a higher maximum carried voltage should help you charge your portable devices more quickly.
It sounds great--and recently it seemed poised to make its debut. Asus was scheduled to ship the high-end P6X58 Premium motherboard with USB 3.0 ports provided by NEC's host controller (for the uninitiated, the traffic cop for external devices), but the company announced a slight delay. NEC's host controller just obtained the first USB 3.0 certification of any host on September 21, however, so that Asus board should see the light of day before long.
A few more motherboards equipped with USB 3.0, all using NEC's host controller, should crop up later this year, and Fujitsu is close to releasing a laptop with USB 3.0 ports. USB 3.0 ports will become far more common on laptops and desktop PCs throughout 2010.
All the ports in the world are useless without compatible devices, of course. We saw a demo at IDF 2009 of an external solid-state drive with a USB 3.0 connection by LucidPath that achieved a transfer rate of over 240MB per second (and if you've ever used an external USB hard drive, you'll know just how much faster that transfer rate is). These sorts of mass storage devices should be the first to hit the market, starting early in 2010.
Expect video cameras to start using USB 3.0, too. Point Grey has demonstrated a high-def Webcam that uses USB 3.0, though it isn't yet a shipping product. Unlike current USB Webcams, this USB 3.0 model does not have to compress the video feed before sending it to the PC. SuperSpeed USB is fast enough to transmit the raw, uncompressed HD video to the PC for capture or compression, which can greatly improve the video quality and make high-def Webcams cheaper, too. Devices like these will arrive a little later in 2010, but you should see all sorts of products carrying the SuperSpeed USB label on store shelves by the end of 2010.
None of this means that USB 2.0 is going anywhere, of course; it will continue to be the more affordable option until USB 3.0 controllers come built into the I/O host controllers of motherboards (the NEC USB 3.0 host controller mentioned above is a separate chip on the motherboard, and is not part of the motherboard's main host controller). And USB 2.0 is still suitable for input devices--mice and keyboards don't require all of the available bandwidth that SuperSpeed USB promises.
Still, it's good to know that the higher-speed, lower-power, faster-charging cabled future is almost upon us. Perhaps your future 128GB iPod, Zune, or smartphone won't take 2 hours to fill up with music.