What you could do with this one G is extras ?
Because the likes are on Content and not so say the individual you can expand on new islands, Most liked today, week, month.
What i like if the likes work as in the kudos site i listed is that it brings out the better replies and content from members, they want to expain that bit more, they want to help that bit more and eventully gaining a like.
Not sure why your digging into this method, another concept that could play alongside is "Best answer" which is another type of reward scheme which brings with it possible Extra Likes who knows?
Food for thought.