I have noticed the same problem. A little climb I regularly do still shows my best time as one I did about five weeks ago despite the fact that I have improved on this recently by 29 seconds. I really like the segments and they are a great motivation in training but it is a bit deflating when I really went for a climb and despite a substantial improvement this have not been noted as my fastest time and have not moved me up the leaderboard.
I hope they sort this out soon as it will influence my willingness to upgrade to the Garmin 1000, currently using the 810 but like the idea of live segment updates, though not if they don't work.
