I think it's fair to credit Uri Geller with the effect of metal bending as we now know it. I've never found anything comparable to spoon bending before Uri came along. And I've really searched!
The nearest thing I've found is the bending of cutlery as it flew through the air during so called poltergeist or haunting episodes. Not really the same thing. Besides which finding a precedent that is obscure doesn't take away from the fact that it was Uri Geller who gave rise to the popularity of metal bending among mentalists and magicians.
The bending of a metal rod, as mentioned by Jonathan, was a speciality of French psychic Jean-Pierre Girard. But I think Girard's metal bending powers only made themselves known following Uri Geller's rise to fame.
You can see some of it here:
http://www.youtube.com/watch?v=OSWnp8OB ... annel_page
I think Uri was also the first to feature the psychokinetic starting of broken watches.
And while there were many drawing duplication effects before Uri Geller, Uri certainly made it his own and got more out of it than anyone else.
I've always been fascinated with the way psychics create unique and offbeat mentalism effects. They work with interested people, not audiences, and this might aid the evolution and development of effects that fulfil some expectations on the part of the viewers. They feel real. Psychics do very simple things that make tangible a belief or inspire hope.
Then, as magicians, we take them, routine them, add some colourful props and finish on a kicker!