I think getting into the business of making TVs would be a big mistake for Apple. There is demand for a wide array of sizes and features, while Apple would likely only offer two or three configurations at the most. Margins are razor-thin. And some of the best products are made by companies that Apple would have to compete with at the same time as being supplied by them. And when it comes to TVs, the display is a much more significant part of the cost than anything else Apple makes, with the exception of the Cinema/Thunderbolt display, which is widely criticized as being overpriced. In addition, the product life cycle is longer for a TV than it is for most of what Apple sells.
I just don't see how Apple can make a big enough dent in this market to justify the huge cost of developing such a product.