The article is slightlyconfusing, it's not just the Tegra 3, devices must have hardware that supports the new 802.11ac dual band Wifi standard.
For example the Nexus 7 has a Tegra 3 but won't have this since it doesn't do any 5Ghz Wifi.
The Miracast certification being touted by the WiFi Alliance has a new adherent, with NVIDIA announcing that its Tegra 3 display proceesor will support the technology. Miracast is a display mirroring technology pitched against Apple’s AirPlay and Intel’s WiDi, both of which are criticized as single-vendor closed environments. …