The partnerships mobile manufacturers have with providers is why it's going to be hard for a not Brand Name manufacturer to get in the game. Partnerships and negotiations are big, complicated, pure business activities; something the OSS people haven't shown a lot of proficiency in.
It's a classic technology problem, and not indicative of the potential of the hardware, but you've got to talk the talk and walk the walk to get things sold, it isn't just about getting stuff in the shelves. You're going to have to wear suits, play golf and schmooze to get traction with big name providers, in any industry, and most OSS types are pretty terrible at that.
I'm not knocking OSS types, at all, I'm just saying that you've got to have a face to front your efforts. Neither Apple nor Microsoft nor Oracle nor Google would be what they are without a lot of salesmanship going on.