that very nice video...I goto work hard to make my arm work as smoothly as those ones!!! Yes I can! but my mind is following two different thing s at the same time...not too good...I think it should be fine, the accuracy required isn't massive, the electromagnet should pick up off centre pieces and it doesn't matter that much if they aren't placed exactly at the centre of the square.
This one looks like hobby servos and it's pretty impressive.
http://www.youtube.com/watch?v=zV6EqS9Zrwo
I'll comment the prevoius post very soon...
I am reading that wikipedia link...
thanks!