Honestly there's no reason this couldn't be done. Like already said, you just need electromagnets, but rather than modifying the ski, you could route out the toe and heel of the ski boot, but metal plates in, and have cables that run to some kind of battery in a small backpack - wouldn't have to be small at all. The backpack would power the electromagnets, and you would have a wireless relay on top of your pole, or like on your glove so if you touch your pointer and thumb together it would cut the circuit (obviously this bit might need refining - I wouldn't want to be wiggling my cold fingers and drop a ski on some poor kid by accident). When you release, the circuit would automatically go back on, so you only need to press to release the ski, then it would snap back on it's own (may need some sort of alignment aid).
As for the ski, all that you'd need would be basic metal plates mounted in place of bindings - nothing fancy at all.
VOILA