There are people that use the iPad to watch video in the gym while there are straining and grunting on the torture machines, while others love to have the iPad on their chest while in bed to view movies.
In the US there are the Netflix and Hulu type of options while elsewhere you can easily have your video content on your computer and stream it wirelessly to your iPad using apps like AirVideo or Zumocast. I have tried both of these applications and for the moment I prefer Zumocast.
What I like about Zumocast is the ease of use. It is easy to run the server application on the desktop computer and easy to find the movie you want to see on the iPad. It is not long, after a little buffering, before you are watching whatever film you have chosen. AirVideo application does much the same although it does have the extra feature in that it will do a sweet conversion job to exactly the right format of your movie so you can download onto your iPad ready to watch when not able to stream to it.
For some people the iPad is the first truly convergent Television / computer, despite being a completely new category of device. With it being able to be chameleon in the way it becomes whatever you want it to be, the iPad can be all things to all men or women or geek. The humble television could have been so much more if the manufacturers had put in more features and gone more done the convergence route than they have done so far.