I can confirm Spotify now works perfectly well on Chromecast
xfinity and hbogo are great too
I love using HBO Now on my Chromecast but man is it a bear to fast forward and reverse using the iPhone app.
It's not any better on Android, and Hulu isn't any better either (but they do have an ad-free subscription now, which makes them actually nice to use finally).
I don't know why they don't just add time input dialog box on all video apps. Scrubbing just isn't cutting it
Hmm, can you provide more details about the xfinity functionality? As of a week or two ago I wasn't able to find any support for it beyond just generically casting the tab from a PC to chromecast.