I'm using Cocoslive with one of my games. I noticed that one could post the same high score under a different name when I was testing the service. In order to prevent users from doing this, I recorded whether they already sent in a high score to make sure they only sent it in once. Unfortunately, the limitation with this design is that the users can't change the name of the score they posted.
The general model of the current service seems like it could use improvements. It would be nice if there was some unique ID phones could send it when scores are posted (either provided by the phone or cocoslive in a response). That way, when new scores are posted or current scores are updated, this ID could be provided and the records can be matched. This would also be useful in retrieving updated information on scores already posted to the server (in the case that ranks are adjusted as other scores are posted).
Or are people getting around my issue another way?