USB 3.0 is the latest iteration of the USB protocol, which at 5Gbps throughput offers a substantial speed boost over USB 2.0, and gives it more options to host high-bandwidth devices, including video adapters for external displays. While video, networking, and audio over USB is nothing new, the greater bandwidth of USB 3.0 allows for more of these options to be lumped together into rather versatile docks such as Kensington's SD3500V docking station.
Apple began including USB 3.0 in its 2012 iMac and MacBook systems, so people who have these systems may be able to use Kensington's docks directly to expand their systems' capabilities. Kensington not only offers full docking solutions like the SD3500V, but also USB 3.0 video adapters like its Universal Multi-Display Adapter.
While these docks and adapters are USB 3.0 devices, this does not preclude them from being used on systems that only came with USB 2.0. USB 3.0 is backward compatible with USB 2.0, but if your Mac has Thunderbolt connections, then you can use a similar Thunderbolt-based docking solution such as the Matrox DS1 and Sonnet Echo 15 to add USB 3.0 and more capability to your system. In fact, the higher-bandwidth Thunderbolt bus offers a more robust solution than USB 3.0, and can allow users to not only attach a Thunderbolt dock, but also host USB 3.0 devices such as Kensington's solutions through a Thunderbolt-based USB 3.0 port.
Unfortunately USB 3.0 solutions are limited in that they cannot offer other popular ports such as FireWire and eSATA, but the offerings in Kensington's docks should be enough to augment most users' systems quite significantly.
Priced at between $80 and $199, Kensington's USB 3.0 docks and adapters should be compatible with systems running OS X 10.6 and later.