If and when Apple releases an Apple TV that is an actual TV, expect it to be in the 40"-50" size range, not the 50"-60" size range, because Apple would not be price competitive at that size. Realize that though the 27" Cinema Display does have a native resolution of 2560 x 1440 at a $999 price point, scaling the screen to even 40" while maintaining that resolution, while not insurmountable, is technically difficult and will carry a premium price tag. Apple Cinema Displays have the best picture of any display in the world, and you can expect a 40" to be at a higher price point than the best Sony or Samsung 40" display.
Also, expect the Apple TV, as well as slot-load DVD or Blu-ray superdrive, cable card slot, and DVR, to be integrated into the display. Steve Jobs said the problem with Apple TV was that there was no viable 'to-market' strategy, in large part, because of all the different players in the game. There's no nation-wide cable provider. The industry is balkanized. The way around that is to integrate everything into the display. And, it won't be marketed as a TV with integrated Apple TV. It will be marketed as a TV with everything integrated, replacing all the boxes under your TV, with the best picture of any TV in the world.
Apple is the only company that I trust to do this, because they are the only company that understands what the consumer wants from the experience and has the will to deliver that experience. I have a Sony TV in my bedroom with a slot-load DVD player with power supply mounted to the back. It is a lower-end model without the integrated Bravia internet, so I most likely will also be strapping an Apple TV to the back of my TV as well. I have a small surge-protector strapped to the back because the wall plate only has one outlet. So, I have had to get all these boxes mounted around the back of the TV with a flat wall mount. I'm a minimalist. The only furniture in my bedroom is a bed and two night stands (if I had it my way, there would be just the bed, but my partner wouldn't have it). I don't have anywhere else to put all these boxes. It would have been far better for me if Sony had realized that consumers want all of this functionality but without all the clutter and had the will to put it all in the TV.