As Android 4.2 Jelly Bean+ appears on the Samsung Nexus 10 tablet and the LG Nexus 4, so too does wireless mirroring to device compliant with Miracast - a standard wireless technology that's not quite hit the market yet. Of course there are some devices that have been revealed already, but it's important that you understand that if you've got a Nexus device - or just want to use Miracast for all your wireless needs - that you don't just go buying anything with the word "Miracast" attached to it. We're still in the wild west, as it were.
This is essentially a PSA here - don't trust everyone at the moment when it comes to the word Miracast being tossed around. Some devices have been released pre-compliant, that meaning they're able to see one another to a degree, but wont be able to connect without a hitch. Instead what you should be checking is - SlashGear, of course - but also the Wi-Fi Alliance's listing of all devices they have certified Miracast compliant.
NOTE: We've gone through this information in a slightly different manner previously in a post entitled How does Android 4.2 Jelly Bean wireless display mirroring work?
This list is extremely short at the moment and is limited to an upcoming Echo-P Series Samsung TV, some components that go into TVs in the near future, and a few adapters from various companies. Keep your eyes open for an Actiontec ScreenBeam Wireless Display Adapter, LG Media Dongle, and a Sony Corporation USB Wireless Adapter Module. Each of these products will likely hit the market in 2013.
For now you are, again, in the wild west. This means that you can get products that say they're "pre-certified Miracast" and have the technology, but are not guaranteed to work with future products. Or current products, in some cases. The two Nexus devices that were just revealed by Google work with Miracast for wireless media mirroring and both the LG Optimus G and the Samsung Galaxy S III are ready for action now as well - now we just need the other end!