It's predominantly cosmetic, but the above message isnt working properly for me anymore.
When I favorite a post it initially displays as per usual, but if I revisit the thread it counts me in as "x people have marked this as a favorite", leading me to re-favorite posts from time to time (at which point it changes to "You and x-1 people have marked this as a favorite").
Not a big deal, but I figured it might be a symptom of something more important.