On April 12 I answered a question (about the usage of "awhile") which was, a bit to my surprise, accepted by the asker (Brandon Boone). Ten days later the asker decided that he preferred another answer to the question, which had been given on the same day as mine.
I've read the answer given to ADVS89 for the question "Changing accepted answer" (27 March 2011), so I've learnt that this shift can be done at any time and the reputation points are taken and given accordingly.
As I don't think this is completely fair, I would suggest introducing a kind of "protection" for the originally accepted reply (and for the reputation of the person who supplied it) by not taking away the points after a period of, say, one month acceptance, or at least leave part of the points (for example, take away 10 out of 15 points).
I'd like to hear what you think about it. Thank you for your time.