One of the most annoying thing about these devices is that because the lack of storage, they need to be streaming all the time (which is a problem with connections with a cap like in Canada) which is very inconvenient if you want to buy movies on iTunes/Google Play.
AppleTV enables game devs to use the TV as a separate common screen for multi users games but that feature seems to be missing with the Chromecast (or at least I couldn't find any reference to it)
So as an AppleTV owner I just can't help but to think this as a "meh"