Tablet devices offer screen space almost equivalent to a decently sized computer monitor. The TWiTpad app is therefore able to offer various additional elements along with the standard video, which provides interaction with the live shows.
Not Just Video
The TWiT network (which stands for This Week in Tech) covers as the name suggests various technology related topics with a few shows that drift into other areas. These presentations are streamed live over the Internet and so of course the TWiTpad app allows you to view this video.