I just got the updated chromecast app which allows for screen mirroring. Only problem is...IT DOESN'T WORK WITH THE NOTE 2. There went my short-lived excitement. Sheesh!
EVERYTHING in Google is usually "Beta". Some things are in beta with them for years.
Because I couldn't mirror from my phone, I tried chromecasting from my PC and Chrome browser. That was awful. Many dropped frames and frame rate looked like it was under 10 FPS. When I chromecast Netflix from my phone, it's awesomely good. sigh. Maybe it's the distance from my PC to the chromecast dongle?