This looks promising and is certainly needed in a market dominated by a $30 Chromecast. I do wonder about the quality of it all - as a Flame reference device owner I know first hand how immature Firefox OS is (dropped calls, random reboots, missing basic everyday functionality). Isn't the platform too young to go beyond phones?
FWIW, I use a Flame as my day-to-day phone and I haven't had any problems with dropped calls or random reboots or other bad behaviour. It's a fairly solid phone, in my experience.
(I'm not saying your aren't having these problems; I'm just saying that not everyone has these problems.)
The Flame is my day-to-day phone as well. I got it a few weeks back and was very stoked to try it out. The phone came with Firefox 1.3 installed and it had quite a few issues -- not logging missed calls, multitasking view not working, slow browser speeds. I blogged about my experience and got a Twitter reply [1] from a Mozillian to give Firefox OS 2.1 a spin. A couple of days later I flashed the 2.1 image on the phone and, unfortunately, it created more problems than it solved. The dialer will randomly lock up not allowing you to call a number, on incoming calls the slider will not react and you can't answer, quite often with no usage at all the phone will reboot out of the blue. Overall 2.1 and 2.2 and very unstable and appear to improve on visuals only. I.e., you get more polish, but a less usable phone.
Hence why Firefox OS may be too young to move beyond the phone. They should focus more on testing and stability in order to have a reliable foundation to build upon.
