If however you want online highscores so people can compete with other people, then your best bet is to incorporate Kongregates online scoreboards, or facebook plugin for scores. However a lot of people have tried and failed.
AJTilley, can you explain a bit more on how they failed in implementing the facebook highscores?
I am intending to make a highscore system similar to that of Angry Birds Friends and some pointers in how to do that would be helpful ;]
<img src="http://cdn.pocket-lint.com/images/GbcR/angry-birds-friends-arrives-on-facebook-0.jpg20120523-191353" border="0" />