It appears that updating the reputation shown for users on per-site meta sites stopped working sometime yesterday. (I think I have it narrowed down to a span of a few hours.) Here are the data points I've observed:
Can we narrow it down at all? This user's meta profile reflects some but not all rep earned yesterday. The last 15 points earned yesterday (and the 10 earned today) are not counted, so the syncing probably stopped working (on that site) between 13:46 and 17:15 yesterday.