A friend of mine worked at a marketing agency where she worked with a prototype system similar to this, howeverit was even more interactive. At any given time during a show, you could:

1) Hit the pause button

2) Point the remote at the TV which controles a mouse like cursor (think Wii Remote)

3) Point to car\shirt\bag\etc that happened to be on the screen at the time

4) Click it and be directed to a 'buy it now' interface

The idea is that companies would pay the show for product placement adding to the revenue of the show and ... dare I say... eliminate the need for commercials.

The only problem I foresee with this approach is increasingly blatant product placement within shows which WILL get to the point of being distracting, much like commercials are today.