Little, black, different

Given how many TV manufacturers have been rumbling about including AirPlay support, that's not too unlikely.

Microsoft had some standard for wireless projectors that I've never seen in real life, but hopefully this will catch on.

Kinda depends on who you are. There's a high ratio, say 1 to 20, of people who want to build their own media center versus people that just want to buy something cheap that works well. I've built my own media centers before, but honestly when the first Apple TV came out a few years ago it answered pretty much every problem I had. I was able to buy tv shows and rent movies right from my TV. The interface was pretty straightforward. I used to pirate movies and shows, but that was a lot more complicated than just spending a couple bucks to get something to watch right now. Didn't have to worry about poor quality anymore, etc.

I really like to reverse your question: why would anyone want to build their own media center now-a-days?

It's $100, plug-and-play, and you can quickly and easily pay for things to watch. It's a product, not a lifestyle.