Now I've been away from some time but this particular story caught my eye.
Lots of hot air has been generated by UGC and more lately 3D - this sort of targetting could be the saviour of commercial TV (or not).
Interesting that Sky are the ones running with it.
Adverts that are relevant have been touted for some time and it seems that the UK will be geting them from 2011
Here's the story