[citation][nom]icrf[/nom]Is this Miracast? If not, what's the difference? I'm a little fuzzy on the features of all these various protocols.[/citation] Yes and no. Miracast is like Airplay, fairly obvious screen mirroring. This will also support two-way comms for more advanced dual-screen uses (one possibility would be, fire up a movie on your TV, and your tablet displays a catalogue of chapters and play/pause controls, info about the movie, etc).
DLNA is not a 'push' technology. You have to 'pull' the content from the DLNA source via the device you want to watch the media on. It's not very widely supported, not well implemented and sometimes does not work very well.
[citation][nom]zybch[/nom]For gods sake, stop reinventing an already existing and working standard and just make your devices support DLNA properly already!![/citation] Idiot. While proper, widespread working DLNA implementations would be nice (instead of the piecemeal mish-mash we have today), this would not be like any existing protocol. I would prefer we pushed for new things, pushed for improvement, rather than squatting around sort-of-OK solutions, wouldn't you?? Google has the clout to make this thing catch on. That it is an open design and presumably free to use, unlike some of these other solutions (Miracast, Airplay) is a big factor in this too.