Concert Calendar Woes

It's been frustrating to notice that some changes to the Concert Calendar listing on the right are not reflected here. The calendar is a Google Calendar that is synced to iCal, which I use to enter information. Lately, I've been observing that some updates made in iCal are not syncing properly - hence, some new and updated information may be missing. I've noticed this with other, personal calendars that I maintain. I'll make sure that all information listed is correct, but right now I have little confidence in Google Calendar's syncing function.