I agree with your assessment that there will be no dominant player in internet TV but I do think Apple needs to decide soon if the ATV will continue to be a hobby or a real product with the appropriate marketing support and expanded entertainment options.
This will really depend on how profitable ad-supported apps are. With the App store, the developer gets to set his price and take his cut while most Android apps rely on those ads. Does anyone know what the typical payout is for an impression from Google ads?
Too much is made of marketshare alone and even Apple has been guilty lately of blowing up the importance of this number. What I like about Apple is its outsized profitability relative to its marketshare in most its product categories.