Im against it on the whole.
For decisions involving the ball crosing the goal line, there is a viable case. But when you start to go down the road of 'Video referees' ala Super League (which actually works very well) In that particular sport...the intuitive nature of this fast moving spectacle and some of the passion/spontenaiety involved may start to get diluted.
The subject of Video technology might well be a grand idea to have its own thread. Should anyone have enough to say on the matter and the inclination to create one.