I just got back from a run and synced my Forerunner 620 via WiFi. The transfer completed, but when I logged into Garmin Connect, the activity wasn't there. I synced again with the USB cradle, and the activity still did not appear in Connect. I just now tried uploading the FIT file manually, and Connect is hanging on Uploading...
I also tried transferring my personal records to the 620, on which I did a master reset last week after the watch rebooted at the end of a workout. Connect opened Garmin Express to do the transfer but it hung while preparing the file, and the file modification date did not change on the watch filesystem, so it had not yet reached the point of writing data to the watch.
Makes me wonder whether part of the site's back end has crashed. Has anyone else noticed this problem?