In the last week, Google has released a beta version of the Chromecast OS. With this update, they removed all Chrome branding within the OS. This might have something to do with the event that Google is hosting next week. According to Android Police the boot image on the new Chromecast OS has the Google logo instead of the Chrome logo.
A new Chromecast has also been leaked, with this the rumor is that it will support 4K and run Firmware 1.21 at launch. Priced at $69 it will about double what the current chromecast costs.