Fact is, I can find nothing conclusive on Miracast or how it works in 4.2.
The only Google literature I can find touts 4.2 as Miracast enabled and makes no distinction about what devices it will, or will not, work on.
If you could target something offical to read about Mircast and 4.2, i would be grateful.
disappointing , Miracast in 4.2 is a myth. Months away, at best.
The holy grail is seemless interface with TV by tablet and Phone. We all just want to turn on Miracast and see our screen on our 55" HD TV's.
Android 4.1 & 2 has been a step backwards with respect to TV interface, i at least had a remote control app which worked before Jelly Bean. My Samsung Remote App which worked with ICS no longer works and I am relegated to typing (on smart TV) with my TV remote.
Now Miracast does nothing.
Apple is light years ahead and they don't false advertise quite as much as Google.
My 1.5 year old laptop with Intel WiDi (Intel Wireless Display) interfaces to the TV but not my brand new Android 4.2 Nexus 10 or Galaxy Nexus with 4.2.
"The Galaxy Nexus lacks the Miracast screen sharing ability, but as of today that doesn't matter much because there's no equipment that works with it."