The following talk in the Changing Media Summit was a pleasure: quick (108 slides in 20 min!), witty, interesting, and well done. The title was "The Revolution will not be televised: Media and Technology move outside the Box" by Suranga Chandratillake, CEO and founder of Blinkx, a video search engine.
The main point of the talk was that in TV over web, technology allows a change of medium but that the media is still the same. From then, he went through a couple of relevant analogies looking at the arrival of radios in every household, in the 1920's advertised as "The newspaper that comes through your walls!". The second example was the arrival of cable TV in the US, with a wealth of interesting information and anecdotes I'm not going to go through now, except for this one: HBO aka "Hey Beastmaster's On".
In the end Web and TV are a different medium, so the question raised is how to combine them? Well for one, people are already doing it. If you think of it, you must have at some point been watching TV with your laptop, and had a thought that you could check the actor's name on imbd, for example. So it's all in it's infancy, it will take time to find out what kind of medium we'll be using in the future, but what's already certain is that the medium will be interchangeable / interconnected and the media will have endless amounts of content everywhere.