I just found a link to a project Intel is developing in Open Source for real time image recognition.
Now this may seem like something that can only be used in things like security systems or robotics but what if you linked it up with something like F-spot or Picasa. While it is trawling your photos extracting meta data, it could also look at the picture and see who in there matches say photos in your address book and adds the appropriate tags. It could also possibly pick out background objects (like mountains or the beach) and create sets of photos that relate to each other.
The same thing could be done for home movies.
I also wonder if you use it in some interesting security situations. Like if your PC knows that you are on a banking website but the person sitting logged as you is someone else, it would start recording the screen and camera views.
Anyway, back to work.